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39 results on '"Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599)"'

1. Coupling and Dearomatization of Pyridines at a Transient η2 -Cyclopropene/Bicyclobutane Zirconocene Complex

Author: Chiara Dinoi, Laure Vendier, Michel Etienne, Quentin Dufrois, Nuria Romero, Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT-FR 2599), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: pyridine, [PHYS]Physics [physics], 010405 organic chemistry, Stereochemistry, Ligand, Organic Chemistry, zirconium, General Chemistry, cyclopropene, coupling reactions, Cyclopropene, 010402 general chemistry, 01 natural sciences, Catalysis, Coupling reaction, 0104 chemical sciences, Cyclopropane, chemistry.chemical_compound, Stereospecificity, chemistry, Pyridine, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Selectivity, cyclopropyl, Bicyclobutane
Abstract: bibtex: ISI:000414633200027 bibtex\location:'POSTFACH 101161, 69451 WEINHEIM, GERMANY',publisher:'WILEY-V C H VERLAG GMBH',type:'Article',affiliation:'Etienne, M (Reprint Author), CNRS, LCC, 205 Route Narbonne,BP44099, F-31077 Toulouse, France. Etienne, M (Reprint Author), Univ Toulouse, UPS, INPT, LCC, F-31077 Toulouse, France. Romero, Nuria; Dufrois, Quentin; Vendier, Laure; Dinoi, Chiara; Etienne, Michel, CNRS, LCC, 205 Route Narbonne,BP44099, F-31077 Toulouse, France. Romero, Nuria; Dufrois, Quentin; Vendier, Laure; Dinoi, Chiara; Etienne, Michel, Univ Toulouse, UPS, INPT, LCC, F-31077 Toulouse, France. Romero, Nuria, Univ Autonoma Barcelona, Dept Quim, Cerdanyola Del Valles Ba 08193, Spain. Dinoi, Chiara, LPCNO INSA, 135 Ave Rangueil, F-31077 Toulouse, France.','author-email':'michel.etienne@lcc-toulouse.fr',da:'2018-12-05','doc-delivery-number':'FM0EI',eissn:'1521-3765','funding-acknowledgement':'MENESR [ANR-11-BS07-0009]; COST Action CHAOS [CA15106]','funding-text':'We thank the MENESR for a PhD grant to QD, the ANR (Green-LAkE project; ANR-11-BS07-0009) and COST Action CHAOS (CA15106) for support.','journal-iso':'Chem.-Eur. J.','keywords-plus':'AROMATIC N-HETEROCYCLES; CH BOND ACTIVATION; CRYSTAL-STRUCTURES; ALKYL COMPLEXES; H BONDS; METAL; CHEMISTRY; ETA(2)-CYCLOPROPENE; ORGANOZIRCONIUM; NIOBIUM','number-of-cited-references':'42','orcid-numbers':'Romero, Nuria/0000-0002-2704-7779 Vendier, Laure/0000-0002-7111-9258 Etienne, Michel/0000-0002-1099-3232','research-areas':'Chemistry','researcherid-numbers':'Romero, Nuria/A-9756-2016','times-cited':'0','unique-id':'ISI:000414633200027','usage-count-last-180-days':'4','usage-count-since-2013':'12','web-of-science-categories':'Chemistry, Multidisciplinary'\; International audience; This paper reports on stereospecific coupling reactions between an (2)-cyclopropene ligand and pyridine derivatives, which are preferred to alternative C-H bond activation reactions. The dicyclopropylzirconocene complex [Cp2Zr(c-C3H5)(2)](1) eliminates cyclopropane to generate the (2)-cyclopropene/bicyclobutane intermediate [Cp2Zr((2)-c-C3H4)](A). A does not activate any pyridine C-H bonds, but rather pyridine inserts into a Zr-C bond of A, yielding an azazirconacycle with a dearomatized pyridyl group [Cp2Zr\(2)-N,C-8-(2-c-C3H4)-C5H5N\](2). Kinetic data, isotopelabelling experiments, and DFT calculations indicate that the rate-determining step of this stereospecific reaction is cyclopropane elimination, and that the stability of the intermediate [Cp2Zr((2)-c-C3H4)(NC5H5)](A-py) governs the selectivity of the reaction. Complex2 tautomerizes to [Cp2Zr\(2)-N,C-8-(2-C3H5)-C5H4N\](6) through a base-catalyzed proton migration accompanied by cyclopropyl opening and restoration of conjugation within the zirconacycle.
Published: 2017

2. Synthesis of Water-Soluble Palladium Nanoparticles Stabilized by Sulfonated N-Heterocyclic Carbenes

Author: Ernesto de Jesús, Yannick Coppel, Simon Tricard, Bruno Chaudret, Juan M. Asensio, Román Andrés, Departamento Química Orgánica y Química Inorgánica, Universidad de Alcalá, Alcalá de Henares, Universidad de Alcalá - University of Alcalá (UAH), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie de coordination (LCC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: organometallic chemistry, 010405 organic chemistry, Organic Chemistry, Thermal decomposition, Inorganic chemistry, chemistry.chemical_element, Nanoparticle, General Chemistry, palladium, 010402 general chemistry, 01 natural sciences, Decomposition, Catalysis, 0104 chemical sciences, Styrene, n-heterocyclic carbene ligands, chemistry.chemical_compound, chemistry, nanoparticles, [CHIM.COOR]Chemical Sciences/Coordination chemistry, aqueous phase, Carbene, Organometallic chemistry, Palladium
Abstract: International audience; A strategy involving the decomposition of palladium(II) organometallic complexes with sulfonated N‐heterocyclic carbene ligands leads to the formation of stable and water‐soluble Pd nanoparticles. Three different methodologies (thermal decomposition, reduction under 13CO atmosphere, and reduction with H2) gave particles with different shapes and sizes, ranging from 1.5 to 7 nm. The structures of the organometallic intermediates and organic decomposition products were elucidated by NMR spectroscopy. To check the accessibility of the surface, the nanoparticles were tested as catalysts for the chemoselective hydrogenation of styrene in water. An effect of the particle size on the catalyst activity was observed. The aqueous phase was recycled up to ten times without any precipitation of metallic palladium.
Published: 2017

3. Trinuclear Cyanido‐Bridged [Cr 2 Fe] Complexes: To Be or not to Be a Single‐Molecule Magnet, a Matter of Straightness

Author: Jean-Pascal Sutter, Céline Pichon, Carine Duhayon, Nathalie Guihéry, Valentin Jubault, Nicolas Suaud, Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Systèmes étendus et magnétisme (LCPQ) (SEM), Laboratoire de Chimie et Physique Quantiques Laboratoire (LCPQ), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), ANR-17-CE07-0007,AnisoChirMag,Anisotropie Optique au sein d'Aimants Moléculaires Chiraux: Vers une Lecture Optique de l'Orientation du Spin(2017), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: Steric effects, 010405 organic chemistry, Chemistry, Magnetism, Organic Chemistry, Relaxation (NMR), General Chemistry, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Magnetization, Crystallography, Magnetic anisotropy, Pentagonal bipyramidal molecular geometry, Single-molecule magnets, Anisotropy, Moiety, Single-molecule magnet, Ab initio calculations, Pentagonal bipyramid
Abstract: International audience; Trinuclear systems of formula [{Cr(LN3O2Ph)(CN)2}2M(H2LN3O2R)] (M=MnII and FeII, LN3O2R stands for pentadentate ligands) were prepared in order to assess the influence of the bending of the apical M−N≡C linkages on the magnetic anisotropy of the FeII derivatives and in turn on their Single-Molecule Magnet (SMM) behaviors. The cyanido-bridged [Cr2M] derivatives were obtained by assembling trans-dicyanido CrIII complex [Cr(LN3O2Ph)(CN)2]− and divalent pentagonal bipyramid complexes [MII(H2LN3O2R)]2+ with various R substituents (R=NH2, cyclohexyl, S,S-mandelic) imparting different steric demand to the central moiety of the complexes. A comparative examination of the structural and magnetic properties showed an obvious effect of the deviation from straightness of the M−N≡C alignment on the slow relaxation of the magnetization exhibited by the [Cr2Fe] complexes. Theoretical calculations have highlighted important effects of the bending of the apical C−N−Fe linkages on both the magnetic anisotropy of the FeII center and the exchange interactions with the CrIII units.
Published: 2021

4. Stuffed Tridymite Structures: Synthesis, Structure, Second Harmonic Generation, Optical, and Multiferroic Properties

Author: Srinivasan Natarajan, Anupam Bhim, Jean-Pascal Sutter, Jagannatha Gopalakrishnan, Solid State and Structural Chemistry Unit, Indian Institute of Science, Indian Institute of Science, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Inorganic pigments, 010402 general chemistry, Second harmonic generation (SHG), 01 natural sciences, Catalysis, symbols.namesake, Tridymite, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Multiferroics, Optical properties, 010405 organic chemistry, Rietveld refinement, Chemistry, Structure elucidation, Multiferroic materials, Organic Chemistry, Second-harmonic generation, Tetrahedral molecular geometry, Tetrahedral geometry, General Chemistry, Ferroelectricity, 0104 chemical sciences, Stuffed tridymite, Crystallography, symbols, Raman spectroscopy, Powder diffraction
Abstract: International audience; The stuffed tridymite structure Ba(Zn/Co)1−xSi1−xM2xO4 (M=Al3+ and Fe3+) is explored for the possible multiferroic behavior and to develop new inorganic colored materials. The compounds were synthesized by employing conventional solid-state chemistry methods in the temperature range 1100–1175 °C for 24 h. The powder X-ray diffraction (PXRD) and Rietveld refinement studies indicate that the compounds stabilize in the P63 space group (no. 173). The refinement results were also rationalized by employing Raman spectroscopic studies. The compounds were found to be second harmonic generation (SHG) active and show weak ferroelectric behavior. The co-substitution of Co2+ and Fe3+ in the structure gives rise to a weak ferromagnetic behavior to the compound, BaCo0.75Si0.75Fe0.5O4, making it a multiferroic material. The optical studies on the prepared compounds exhibited blue color (Co2+ in Td geometry), purple color (Ni2+ in Td geometry), and simultaneous substitution of Co2+ and Fe3+ gives rise to blue-green color owing to metal-to-metal charge transfer (MMCT) effect.
Published: 2021

5. Core carbo ‐mer of an Extended Tetrathiafulvalene: Redox‐Controlled Reversible Conversion to a carbo ‐Benzenic Dication

Author: Carine Duhayon, Ole Hammerich, Dymytrii Listunov, Albert Poater, Gabriel Ramos-Ortiz, Valérie Maraval, Mie Højer Larsen, Irving Caballero-Quintana, Mogens Nielsen, José-Luis Maldonado, Cécile Barthes, Remi Chauvin, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), University of Copenhagen = Københavns Universitet (KU), Consejo Nacional de Ciencia y Tecnología [Mexico] (CONACYT), Centro de Investigaciones en Optica (CIO), Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona (IQCC), Universitat de Girona (UdG), IDEX Emergence program 2014 (carbodevice project), Centre National de la Recherche Scientifique (CNRS), French-Mexican International Associated Laboratory (LIA) 'Molecular Chemistry with Applications in Materials and Catalysis'/ CNRS - CONACyT, ECOS Nord program M16P02 'Carbo-meric Chromophores for Two-Photon Absorption', 2017–2021, and CONACyT grant #291434 'Absorcion optica no lineal en nuevos materiales organicos: el caso de cromoforos carbomeros' 2017–2021
Subjects: Extended tetrathiafulvalene, Redox behavior, 010405 organic chemistry, Organic Chemistry, Aromaticity, General Chemistry, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, Dication, chemistry.chemical_compound, Crystallography, Radical ion, chemistry, Highly oriented pyrolytic graphite, carbo-mer, Quinoid, Carbo-mer, Molecule, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Cyclic voltammetry, Tetrathiafulvalene, Alkyne
Abstract: International audience; Carbo -benzene is an aromatic molecule devised by inserting C 2 units within each C-C bond of the benzene molecule. By integrating the corresponding carbo -quinoid core as bridging unit in a p -extended tetrathiafulvalene (exTTF), it is shown that a carbo -benzene ring can be reversibly formed by electrochemical reduction or oxidation. The so-called carbo -exTTF molecule was thus experimentally prepared and studied by UV-visible absorption spectroscopy and cyclic voltammetry, as well as by X-ray crystallography and by scanning tunneling microscopy (STM) on a surface of highly oriented pyrolytic graphite (HOPG). The molecule and its oxidized and reduced forms were subjected to a computational study at the density functional theory (DFT) level, supporting carbo -aromaticity as a driving force for the formation of the dication, radical cation, and radical anion. By allowing co-planarity of the dithiolylidene rings and carbo -quinoidal core, carbo -exTTFs present a promising new class of redox-active systems.
Published: 2020

6. Central (S) to Central (M=Ir, Rh) to Planar (Metallocene, M=Fe, Ru) Chirality Transfer Using Sulfoxide‐Substituted Mesoionic Carbene Ligands: Synthesis of Bimetallic Planar Chiral Metallocenes

Author: Miguel A. Sierra, Heinz Gornitzka, María C. de la Torre, Marta G. Avello, Catherine Hemmert, Centro de Innovación en Química Avanzada (ORFEO−CINQA Network) (ORFEO−CINQA), Instituto de Química Orgánica General (IQOG), Consejo Superior de Investigaciones Científicas [Spain] (CSIC), Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Ministro de Ciencia, Innovacion y Universidades (MICIUN) of Spain (grants CTQ2016-77555-C2-1-R, CTQ2016-77555-C2-2-R, CTQ2016-81797-REDC Programa Redes Consolider), Fundacion Ramon Areces (grant from the XVIII Concurso Nacional de Ayudas a la Investigacion en Ciencias de la Vida y de la Materia - CIVP18A3938), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Ministerio de Economía y Competitividad (España), and Fundación Ramón Areces
Subjects: Chirality transfer, Metallocenes, 010405 organic chemistry, Organic Chemistry, Mesoionic, Sulfoxide, General Chemistry, Circular dichroism, Planar chirality, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, chemistry.chemical_compound, Crystallography, chemistry, Ferrocene, Sulfoxides, Ruthenocene, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Chirality, Chirality (chemistry), Metallocene, Carbene
Abstract: Enantiopure bimetallic systems containing three different elements of chirality, namely a main-group-based chiral center (sulfur), a transition-metal chiral center (rhodium or iridium), and a planar chiral element (ferrocene or ruthenocene), have been prepared by a sequence of diastereoselective reactions. The chirality of the chiral sulfur center attached to C-5 of a 1,2,3-triazolylidene mesoionic carbene (MIC) ligand coordinated to a metal (Ir, Rh) was transferred through the formation of bimetallic complexes having a chiral-at-metal center and a planar chiral metallocene by C−H activation of the sandwich moiety (M=Fe, Ru). The sense of the planar chirality formed in this sequence of reactions depended on the nature of the ligands at the metal center of the starting complex. The configurations of these species were assigned on the basis of a combination of X-ray diffraction and CD measurements. An electrochemical study of these bimetallic complexes in coordinating solvents showed an equilibrium between the cationic complexes and the neutral species. The effect of the half-sandwich moiety on the oxidation potentials of the system is remarkable, producing notable cathodic displacements. DFT calculations support these findings., Support for this work from the Ministro de Ciencia, Innovaciónn y Universidades (MICIUN) of Spain (under grants CTQ2016- 77555-C2-1-R (to M.A.S.), CTQ2016-77555-C2-2-R (to M.C.T.), and CTQ2016-81797-REDC Programa Redes Consolider) is gratefully acknowledged. M.A.S. thanks the Fundación Ramón Areces for a grant from the XVIII Concurso Nacional de Ayudas a la Investigación en Ciencias de la Vida y de la Materia (CIVP18A3938).
Published: 2019

7. Concentration‐Dependent Interactions of Amphiphilic PiB Derivative Metal Complexes with Amyloid Peptides Aβ and Amylin**

Author: Sara Lacerda, Éva Tóth, Carlos F. G. C. Geraldes, Inga Relich, Christelle Hureau, Jean-François Morfin, Zoltán Garda, Agnès Pallier, Alexandre C. Oliveira, Saida Majdoub, Centre de biophysique moléculaire (CBM), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Faculty of Science and Technology, University of Debrecen, University of Coimbra [Portugal] (UC), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), French National Research Agency (grant DIVA ANR-16-CE18-0022-01), Fundaçao para a Ciencia e a Tecnologia (FCT), Portugal (programmes UIDB/00313/2020 and UIDP/00313/2020), FEDER/COMPETE 2020-EU, European Project: 638712,H2020,ERC-2014-STG,aLzINK(2015), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), ANR-16-CE18-0022,DIVA,Visualization de l'amylin avec des sondes métalliques pour une imagerie du diabète(2016), Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Jakab Toth, Eva, and Alzheimer's disease and Zinc: the missing link ? - aLzINK - - H20202015-03-01 - 2020-02-29 - 638712 - VALID
Subjects: Biodistribution, Amyloid, [SDV]Life Sciences [q-bio], Amylin, Peptide, 010402 general chemistry, 01 natural sciences, Catalysis, Mice, Alzheimer Disease, Coordination Complexes, [CHIM] Chemical Sciences, Amphiphile, Animals, [CHIM]Chemical Sciences, Tissue Distribution, Surface plasmon resonance, Amylin binding, chemistry.chemical_classification, Amyloid beta-Peptides, 010405 organic chemistry, Chemistry, Organic Chemistry, General Chemistry, Peptide Fragments, 0104 chemical sciences, Islet Amyloid Polypeptide, [SDV] Life Sciences [q-bio], Biophysics, Linker
Abstract: International audience; Metal chelates targeted to amyloid peptides are widely explored as diagnostic tools or therapeutic agents. The attachment of a metal complex to amyloid recognition units typically leads to a decrease in peptide affinity. We show here that by separating a macrocyclic GdL chelate and a PiB targeting unit with a long hydrophobic C10 linker, it is possible to attain nanomolar affinities for both Aβ 1‐40 ( K d = 4.4 nM) and amylin ( K d = 4.5 nM), implicated respectively in Alzheimer’s disease and diabetes. The Scatchard analysis of surface plasmon resonance data obtained for a series of amphiphilic, PiB derivative GdL complexes indicate that their Aβ 1‐40 or amylin binding affinity varies with their concentration, thus micellar aggregation state. The GdL chelates also affect peptide aggregation kinetics, as probed by thioflavin‐T fluorescence assays. A 2D NMR study allowed identifying that the hydrophilic region of Aβ 1‐40 is involved in the interaction between the monomer peptide and the Gd 3+ complex. Finally, ex vivo biodistribution experiments were conducted in healthy mice by using 111 In labelled analogues. Their pancreatic uptake, ~3%ID/g, is promising to envisage amylin imaging in diabetic animals.
Published: 2021
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8. Mutations of Histidine 13 to Arginine and Arginine 5 to Glycine Are Responsible for Different Coordination Sites of Zinc(II) to Human and Murine Peptides

Author: Peter Faller, Sabrina Noël, Denis Testemale, Valentina Borghesani, Emmanuel Guillon, Bruno Alies, Christelle Hureau, Stéphanie Sayen, ChemBioPharm, Université de Bordeaux (UB)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Moléculaire de Reims - UMR 7312 (ICMR), SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-SFR CAP Santé (Champagne-Ardenne Picardie Santé), Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Université de Reims Champagne-Ardenne (URCA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Matériaux, Rayonnements, Structure (MRS), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), European Synchrotron Radiation Facility (ESRF), Institut de Chimie de Strasbourg, Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), European Project: 638712,H2020,ERC-2014-STG,aLzINK(2015), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université de Reims Champagne-Ardenne (URCA)-Institut de Chimie du CNRS (INC)-SFR CAP Santé (Champagne-Ardenne Picardie Santé), Université de Reims Champagne-Ardenne (URCA)-Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS)-SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS), Matériaux, Rayonnements, Structure (NEEL - MRS), and Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Arginine, Glycine, Mutagenesis (molecular biology technique), chemistry.chemical_element, Peptide, Zinc, 010402 general chemistry, 01 natural sciences, Catalysis, Mice, Alzheimer Disease, Coordination Complexes, [CHIM]Chemical Sciences, Animals, Humans, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Histidine, Binding site, Nuclear Magnetic Resonance, Biomolecular, chemistry.chemical_classification, Amyloid beta-Peptides, Binding Sites, 010405 organic chemistry, Organic Chemistry, Bioinorganic chemistry, General Chemistry, Hydrogen-Ion Concentration, 0104 chemical sciences, X-Ray Absorption Spectroscopy, chemistry, Biochemistry, Mutagenesis, Site-Directed, Copper
Abstract: International audience; Because mice and rats do not naturally develop Alzheimer's disease, genetically modified animals are required to study this pathology. This striking difference in terms of disease onset could be due to three alterations in the murine sequence (R5G, Y10F and H13R) of the amyloid‐β peptide with respect to the human counterpart. Whether the metal‐ion binding properties of the murine peptide are at the origin of such different amyloidogenicity of the two peptides is still an open question. Herein, the main zinc binding site to the murine amyloid‐β at physiological pH has been determined through the combination of several spectroscopic and analytical methods applied to a series of six peptides with one or two of the key mutations. These results have been compared with the zinc binding site encountered in the human peptide. A coordination mechanism that demonstrates the importance of the H13R and R5G mutations in the different zinc environments present in the murine and human peptides is proposed. The nature of the minor zinc species present at physiological pH is also suggested for both peptides. Finally, the biological relevance and fallouts of the differences determined in zinc binding to human versus murine amyloid‐β are also discussed.
Published: 2018

9. A Rotaxane Scaffold Bearing Multiple Redox Centers: Synthesis, Surface Modification and Electrochemical Properties

Author: Ivan T. Lucas, Emmanuel Maisonhaute, Thi Minh Nguyet Trinh, Iwona Nierengarten, Béatrice Delavaux-Nicot, Suzanne Joiret, Jessem Landoulsi, Jean-François Nierengarten, Alina Latus, Marie Steffenhagen, Laboratoire de Réactivité de Surface (LRS), Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Electrochimie Moléculaire (LEM (UMR_7591)), Université Paris Diderot - Paris 7 (UPD7)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Substances naturelles/chimie moléculaire, Université Louis Pasteur - Strasbourg I-Ecole européenne de chimie, polymères et matériaux [Strasbourg]-Centre National de la Recherche Scientifique (CNRS), Laboratoire Interfaces et Systèmes Electrochimiques (LISE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Labex MiChem (ANR-11-IDEX-0004-02), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Rotaxane, Rotaxanes, Self-assembled monolayers, 010402 general chemistry, Photochemistry, 01 natural sciences, Ultrafast cyclic voltammetry, Catalysis, law.invention, chemistry.chemical_compound, law, Electrochemistry, Molecule, 010405 organic chemistry, Organic Chemistry, Self-assembled monolayer, General Chemistry, 0104 chemical sciences, Ferrocene, chemistry, Intramolecular force, Raman spectroscopy, Surface modification, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Cyclic voltammetry, Scanning tunneling microscope, [CHIM.OTHE]Chemical Sciences/Other
Abstract: International audience; A rotaxane scaffold incorporating two dithiolaneanchoring units for the modification of gold surfaces hasbeen functionalized with multiple copies of a redox unit,namely ferrocene. Surface modification has been first assessedat the single molecule level by atomic force microscopy(AFM) and scanning tunneling microscopy (STM) imaging,while tip enhanced Raman spectroscopy (TERS) providedthe local vibrational signature of the ferrocenyl subunitsof the rotaxanes grafted onto the gold surface. Finally, oxidationof the redox moieties within a rotaxane scaffold graftedonto gold microelectrodes has been investigated by ultrafastcyclic voltammetry. Intramolecular electron hopping isindeed extremely fast in this system. Moreover, the kineticsof charge injection depends on the molecular coverage dueto the influence of intermolecular contacts on molecular motions.
Published: 2018

10. A Cationic Phosphapyramidane

Author: Vladimir I. Minkin, Akira Sekiguchi, Vladimir Ya. Lee, Heinz Gornitzka, Haruka Sugasawa, Ruslan M. Minyaev, Olga A. Gapurenko, Graduate School of Pure and Applied Sciences, University of Tsukuba, Université de Tsukuba = University of Tsukuba, Institute Phys. Org. Chem., Southern Federal University [Rostov-on-Don] (SFEDU), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées
Subjects: 010405 organic chemistry, Chemistry, Computational chemistry, Organic Chemistry, Cationic polymerization, [CHIM.COOR]Chemical Sciences/Coordination chemistry, General Chemistry, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, 3. Good health
Abstract: International audience; Pyramidanes C[C4R4] constitute a novel class of highly strained and reactive polyhedral clusters that attracted a great deal of attention of both theoreticians and experimentalists. Although well-studied from the theoretical viewpoint, pyramidanes were synthetically inaccessible, and only very recently their very first isolable representatives have been described. In this Communication, we report on the synthesis and structural studies of the cationic pyramidane with the Group 15 element at the apex, namely, phosphapyramidane, an isoelectronic analogue of the neutral pyramidanes of the Group 14 elements.
Published: 2016

11. Electronic Structure Modulation in an Exceptionally Stable Non-Heme Nitrosyl Iron(II) Spin-Crossover Complex

Author: Gábor Molnár, Azzedine Bousseksou, M. Carmen Muñoz, Rafael Moreno-Esparza, Lucía Piñeiro-López, Eliseo Ruiz, Jordi Cirera, José Antonio Real, Norma Ortega-Villar, Víctor M. Ugalde-Saldívar, Instituto de Ciencia Molecular (ICMol), Universitat de València (UV), Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Departamento de Física Aplicada, Universitat Politécnica de València, EPSA, Universitat Politècnica de València (UPV), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Recerca de Química Teorica i Computacional, Universitat de Barcelona (UB)-Institut de Recerca de Química Teorica i Computacional, and Universitat Autònoma de Barcelona (UAB)
Subjects: Spin states, Iron, Inorganic chemistry, Antiferromagnetic coupling, Ethylenediamine, Crystal structure, Electronic structure, 010402 general chemistry, 01 natural sciences, Catalysis, Ferrous, chemistry.chemical_compound, Atomic orbital, Spin crossover, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Molecular structures, 010405 organic chemistry, Estructura molecular, Organic Chemistry, Nitric oxide, General Chemistry, Atmospheric temperature range, Òxid nítric, 0104 chemical sciences, 3. Good health, Crystallography, chemistry, FISICA APLICADA, Nitrosyl complexes, Molecular structure, Ferro
Abstract: The highly stable nitrosyl iron(II) mononuclear complex [Fe(bztpen)(NO)](PF6)(2) (bztpen=N-benzyl-N,N',N'-tris(2-pyridylmethyl)ethylenediamine) displays an S=1/2 S=3/2 spin crossover (SCO) behavior (T-1/2=370 K, Delta H= 12.48 kJmol(-1), Delta S=33 JK(-1) mol(-1)) stemming from strong magnetic coupling between the NO radical (S=1/2) and thermally interconverted (S=0 S=2) ferrous spin states. The crystal structure of this robust complex has been investigated in the temperature range 120-420 K affording a detailed picture of how the electronic distribution of the t(2g)-e(g) orbitals modulates the structure of the {FeNO}(7) bond, providing valuable magneto-structural and spectroscopic correlations and DFT analysis., The research reported here was supported by the Spanish Ministerio de Economia y Competitividad (MINECO) and FEDER funds (CTQ2013-46275-P, CTQ2015-64579-C3-1-P, and Unidad de Excelencia Maria de Maeztu MDM-2015-0538) and the Generalitat Valenciana (PROMETEO/2012/049). L.P.L. thanks the Generalitat Valenciana and the Universidad de Valencia for a predoctoral fellowship. J.C. and E.R. thank the Generalitat de Catalunya for a Beatriu de Pinos grant and an ICREA Academia award, respectively.
Published: 2016

12. Coordination Chemistry Inside Polymeric Nanoreactors: Interparticle Metal Exchange and Ionic Compound Vectorization in Phosphine-Functionalized Amphiphilic Polymer Latexes

Author: Eric Manoury, Franck D'Agosto, Rinaldo Poli, Ahmad Joumaa, Muriel Lansalot, Si Chen, Florence Gayet, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie, Catalyse, Polymères et Procédés, R 5265 (C2P2), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), and Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Inorganic chemistry, chemistry.chemical_element, Polymer micelles, Nanoreactor, 010402 general chemistry, 01 natural sciences, Micelle, Catalysis, Coordination complex, Rhodium, chemistry.chemical_compound, Polymer chemistry, Surfaces and interfaces, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Ionic compound, Triphenylphosphine, chemistry.chemical_classification, Ethylene oxide, 010405 organic chemistry, Organic Chemistry, General Chemistry, Nanostructures, P ligands, 0104 chemical sciences, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Phosphine
Abstract: International audience; Stable latexes of hierarchically organized core-cross-linked polymer micelles that are functionalized at the core with triphenylphosphine (TPP@CCM) have been investigated by NMR spectroscopic analysis at both natural (ca. pH 5) and strongly basic (pH 13.6) pH values after core swelling with toluene. The core–shell interface structuring forces part of the hydrophilic poly(ethylene oxide) (PEO) chains to reside inside the hydrophobic core at both pH values. Loading the particle cores with [Rh(acac)(CO)2] (acac=acetylacetonate) at various Rh/P ratios yielded polymer-supported [Rh(acac)(CO)(TPP)] (TPP=triphenylphosphine). The particle-to-particle rhodium migration is very fast at natural pH, but slows down dramatically at high pH, whereas the size distribution of the nanoreactors remains unchanged. The slow migration at pH 13.6 leads to the generation of polymer-anchored [Rh(OH)(CO)(TPP)2], which is also generated immediately upon the addition of NaOH to the particles with a [Rh(acac)(CO)] loading of 50 %. Similarly, treatment of the same particles with NaCl yielded polymer-anchored [RhCl(CO)(TPP)2]. Interparticle coupling occurs during these rapid processes. These experiments prove that the major contribution to metal migration is direct core–core contact. The slow migration at the high pH value, however, must result from a pathway that does not involve core–core contact. The facile penetration of the polymer cores by NaOH and NaCl results from the presence of shell-linked poly(ethylene oxide) methyl ether functions both outside and inside the polymer core–shell interface.
Published: 2016

13. Bis-Sulfonyl O,C,O-Chelated Metallylenes (Ge, Sn) as Adjustable Ligands for Iron and Tungsten Complexes

Author: Luminiţa Silaghi-Dumitrescu, Gabriela Nemes, Petronela M. Petrar, Noémi Deak, Sonia Mallet-Ladeira, David Madec, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut Parisien de Chimie Moléculaire (IPCM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Sulfonyl, chemistry.chemical_classification, Carbon group, 010405 organic chemistry, Chemistry, Aryl, Organic Chemistry, Inorganic chemistry, chemistry.chemical_element, General Chemistry, Tungsten, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, Pincer movement, chemistry.chemical_compound, Oxygen atom, Polymer chemistry, [CHIM]Chemical Sciences, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Chelation, Pincer ligand, ComputingMilieux_MISCELLANEOUS
Abstract: The synthesis and characterization of an E2 CE2 bis-sulfonyl aryl pincer ligand and its efficiency for the stabilization of compounds containing low-valent Group 14 elements (Ge and Sn) are reported. Complexation reaction of these metallylenes with iron or tungsten complexes resulted in the modulation of the oxygen atoms of the sulfonyl groups implicated in the stabilization of the Group 14 elements, demonstrating the original adjustable character of the bis-sulfonyl O2 S-C-SO2 aryl pincer.
Published: 2015

14. Enhanced Activation of Coordinated Dinitrogen with p-Block Lewis Acids

Author: Antoine Simonneau, Michel Etienne, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées
Subjects: 010405 organic chemistry, Chemistry, Organic Chemistry, General Chemistry, 010402 general chemistry, Block (periodic table), 01 natural sciences, Combinatorial chemistry, Catalysis, Frustrated Lewis pair, 0104 chemical sciences, Adduct, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Lewis acids and bases
Abstract: International audience; This Concept article highlights recent research on Lewis acid adducts of dinitrogen complexes, including our contributions. After a reminder of the early works, it is demonstrated that such kind of species offers a new platform for dinitrogen functionalization as well as valuable models for the understanding of elementary steps of (bio)catalytic cycles. When possible, parallels regarding this mode of activation from the orbital point of view are drawn between the different systems discussed herein.
Published: 2018
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15. Calcium Hydride Catalyzed Highly 1,2‐Selective Pyridine Hydrosilylation

Author: Jürgen Pahl, Heiko Bauer, Julia Intemann, Sjoerd Harder, Laurent Maron, Stratingh Institute for Chemistry, University of Groningen [Groningen], Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: calcium, Calcium hydride, 010405 organic chemistry, Hydrosilylation, Hydride, Organic Chemistry, Inorganic chemistry, Magnesium hydride, hydrosilylation, hydride, reduction, General Chemistry, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, Catalysis, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Pyridine, Picoline, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Isoquinoline, Homoleptic
Abstract: International audience; Reaction of the calcium hydride complex (DIPPnacnac‐CaH⋅THF)2 with pyridine is much faster and selective than that of the corresponding magnesium hydride complex (DIPPnacnac = [(2,6‐iPr2C6H3)NC(Me)]2CH). With a range of pyridine, picoline and quinoline substrates, exclusive transfer of the hydride ligand to the 2‐position is observed and also at higher temperatures no 1,2→1,4 isomerization is found. The heteroleptic product DIPPnacnac‐Ca(1,2‐dihydropyridide)⋅(pyridine) shows fast ligand exchange into homoleptic calcium complexes and therefore could not be isolated. Calcium hydride reduction of isoquinoline gave well‐defined homoleptic products which could be characterized by X‐ray diffraction: Ca(1,2‐dihydroisoquinolide)2⋅(isoquinoline)4 and Ca3(1,2‐dihydroisoquinolide)6⋅(isoquinoline)6. The striking selectivity difference in the dearomatization of pyridines by Mg or Ca complexes could be explained by DFT theory and was utilized in catalysis. Whereas hydroboration of pyridine with pinacol borane with a calcium hydride catalyst gave only minor conversion, the hydrosilylation of pyridine and quinolines with PhSiH3 yields exclusively 1,2‐dihydropyridine and 1,2‐dihydroquinoline silanes with 80–90 % conversion. Similar results can be achieved with the catalyst Ca[N(SiMe3)2]2⋅(THF)2. These calcium complexes represent the first catalysts for the 1,2‐selective hydrosilylation of pyridines.
Published: 2015

16. Ruthenium Complexes with Dendritic Ferrocenyl Phosphanes: Synthesis, Characterization, and Application in the Catalytic Redox Isomerization of Allylic Alcohols

Author: Marcel Handke, Hanna Dib, Alix Sournia-Saquet, Toni Grell, Anne-Marie Caminade, Evamarie Hey-Hawkins, Paul Neumann, Institut für Anorganische Chemie, Universität Leipzig, Universität Leipzig [Leipzig], Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: inorganic chemicals, Allylic rearrangement, Denticity, Organic Chemistry, chemistry.chemical_element, Homogeneous catalysis, General Chemistry, Photochemistry, Catalysis, Ruthenium, chemistry.chemical_compound, Ferrocene, chemistry, Polymer chemistry, Moiety, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Isomerization
Abstract: International audience; An efficient system for the catalytic redox isomerization of the allylic alcohol 1-octen-3-ol to 3-octanone is presented. The homogeneous ruthenium(II) catalyst contains a monodentate phosphane ligand with a ferrocene moiety in the backbone and provides 3-octanone in quantitative yields. The activity is increased by nearly 90 % with respect to the corresponding triphenyl phosphane ruthenium(II) complex. By grafting the catalyst at the surface of a dendrimer, the catalytic activity is further increased. By introducing different spacers between ferrocene and phosphorus, the influence on the electronic properties of the complexes is shown by evaluating the electrochemical behavior of the compounds.
Published: 2015

17. A Tris(triazolate) Ligand for a Highly Active and Magnetically Recoverable Palladium Catalyst of Selective Alcohol Oxidation Using Air at Atmospheric Pressure

Author: Laetitia Etienne, Lionel Salmon, Christine Labrugère, Dong Wang, Didier Astruc, Jaime Ruiz, Christophe Deraedt, Institut des Sciences Moléculaires (ISM), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Université Sciences et Technologies - Bordeaux 1-Université Montesquieu - Bordeaux 4-Institut de Chimie du CNRS (INC), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Plateforme Aquitaine de Caractérisation des Matériaux (PLACAMAT), Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Université de Bordeaux (UB), The China Scholarship Council (CSC) of the People’s Republic of China, Ministère de la Recherche et de la Technologie, University of Bordeaux and University of Toulouse 3, The Centre National de la Recherche Scientifique (CNRS), and L’Oréal
Subjects: Heterogeneous catalysis, Organic Chemistry, Inorganic chemistry, chemistry.chemical_element, [CHIM.MATE]Chemical Sciences/Material chemistry, General Chemistry, Photochemistry, 7. Clean energy, Catalysis, chemistry.chemical_compound, X-ray photoelectron spectroscopy, chemistry, Alcohols, Alcohol oxidation, Magnetic properties, Oxidation, Scanning transmission electron microscopy, Azide, Inductively coupled plasma, Palladium
Abstract: International audience; High efficiency and selectivity, easy magnetic recovery and recycling, and use of air as the oxidant at atmospheric pressure are major objectives for oxidation catalysis in terms of sustainable and green processes. A tris(triazolyl) ligand, so far only used in copper-catalyzed alkyne azide cycloadditions, was found to be extremely efficient in SiO2 /γ-Fe2 O3 -immobilized palladium complexes. It was characterized by inductively coupled plasma (ICP) analysis, transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectra (XPS) and found to fulfill the combined conditions for the selective oxidation of alcohols to aldehydes and ketones.
Published: 2015

18. Highly Fluorinated Tris(indazolyl)borate Silylamido Complexes of the Heavier Alkaline Earth Metals: Synthesis, Characterization, and Efficient Catalytic Intramolecular Hydroamination

Author: Yann Sarazin, Nuria Romero, Sonia Mallet-Ladeira, Sorin-Claudiu Roşca, Chiara Dinoi, Laure Vendier, Michel Etienne, Jean-François Carpentier, Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: Agostic interaction, alkaline earth metals, [SDV]Life Sciences [q-bio], Inorganic chemistry, 010402 general chemistry, Metathesis, 01 natural sciences, Medicinal chemistry, Catalysis, chemistry.chemical_compound, Salt metathesis reaction, [CHIM]Chemical Sciences, Homoleptic, ligands, 010405 organic chemistry, Chemistry, Ligand, Organic Chemistry, General Chemistry, 0104 chemical sciences, hydroamination, agostic interactions, Intramolecular force, metathesis, Hydroamination
Abstract: International audience; Heteroleptic silylamido complexes of the heavier alkaline earth elements calcium and strontium containing the highly fluorinated 3-phenyl hydrotris(indazolyl)borate {F12-Tp(4Bo, 3Ph)}(-) ligand have been synthesized by using salt metathesis reactions. The homoleptic precursors [Ae{N(SiMe3)2}2] (Ae = Ca, Sr) were treated with [Tl(F12-Tp(4Bo, 3Ph))] in pentane to form the corresponding heteroleptic complexes [(F12-Tp(4Bo, 3Ph))Ae{N(SiMe3)2}] (Ae = Ca (1); Sr (3)). Compounds 1 and 3 are inert towards intermolecular redistribution. The molecular structures of 1 and 3 have been determined by using X-ray diffraction. Compound 3 exhibits a Sr⋅⋅⋅MeSi agostic distortion. The synthesis of the homoleptic THF-free compound [Ca{N(SiMe2H)2}2] (4) by transamination reaction between [Ca{N(SiMe3)2}2] and HN(SiMe2H)2 is also reported. This precursor constitutes a convenient starting material for the subsequent preparation of the THF-free complex [(F12-Tp(4Bo, 3Ph))Ca{N(SiMe2H)2}] (5). Compound 5 is stabilized in the solid state by a Ca⋅⋅⋅β-Si-H agostic interaction. Complexes 1 and 3 have been used as precatalysts for the intramolecular hydroamination of 2,2-dimethylpent-4-en-1-amine. Compound 1 is highly active, converting completely 200 equivalents of aminoalkene in 16 min with 0.50 mol % catalyst loading at 25 °C.
Published: 2015

19. Efficient and Magnetically Recoverable 'Click' PEGylated γ-Fe2O3-Pd Nanoparticle Catalysts for Suzuki-Miyaura, Sonogashira, and Heck Reactions with Positive Dendritic Effects

Author: Lionel Salmon, Laetitia Etienne, Dong Wang, Didier Astruc, Jaime Ruiz, Christine Labrugère, Christophe Deraedt, Institut des Sciences Moléculaires (ISM), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Université Sciences et Technologies - Bordeaux 1-Université Montesquieu - Bordeaux 4-Institut de Chimie du CNRS (INC), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Plateforme Aquitaine de Caractérisation des Matériaux (PLACAMAT), Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), and Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Université de Bordeaux (UB)
Subjects: Green chemistry, magnetic nanoparticles, Organic Chemistry, Sonogashira coupling, Nanoparticle, chemistry.chemical_element, [CHIM.MATE]Chemical Sciences/Material chemistry, General Chemistry, palladium, 7. Clean energy, Combinatorial chemistry, Catalysis, dendrimers, Nanomaterials, heterogeneous catalysis, chemistry, Dendrimer, Organic chemistry, Magnetic nanoparticles, C--C coupling, Palladium
Abstract: International audience; The engineering of novel catalytic nanomaterials that are highly active for crucial carbon–carbon bond formations, easily recoverable many times, and biocompatible is highly desirable in terms of sustainable and green chemistry. To this end, catalysts comprising dendritic “click” ligands that are immobilized on a magnetic nanoparticle (MNP) core, terminated by triethylene glycol (TEG) groups, and incorporate Pd nanoparticles (PdNPs) have been prepared. These nanomaterials are characterized by transmission electron microscopy (TEM), high-resolution TEM, inductively coupled plasma analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectra and energy-dispersive X-ray spectroscopy. They are shown to be highly active, dispersible, and magnetically recoverable many times in Suzuki, Sonogashira, and Heck reactions. In addition, a series of pharmacologically relevant or natural products were successfully synthesized using these magnetic PdNPs as catalyst. For comparison, related PdNP catalysts deposited on MNPs bearing linear “click” PEGylated ligands are also prepared. Strong positive dendritic effects concerning ligand loading, catalyst loading, catalytic activity, and recyclability are observed, that is, the dendritic catalysts are much more efficient than non-dendritic analogues.
Published: 2014

20. Hetero-tri-spin [2p-3d-4f] Chain Compounds Based on Nitronyl Nitroxide Lanthanide Metallo-Ligands: Synthesis, Structure, and Magnetic Properties

Author: Dai-Zheng Liao, Yungai Li, Xiufeng Wang, Mei Zhu, S. Ramasesha, V. M. L. Durga Prasad Goli, Peng Hu, Jean-Pascal Sutter, Licun Li, Key Laboratory of Advanced Energy Materials Chemistry, Nankai University, Nankai University (NKU), Key Laboratory of Metal and Molecule-based Material Chemistry, Nankai University, Collaborative Innovation Center of Chemical Science and Engineering [Tianjin, China], Solid State and Structural Chemistry Unit, Indian Institute of Science, Indian Institute of Science, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Lanthanide, Nitroxide mediated radical polymerization, 010405 organic chemistry, Stereochemistry, Chemistry, Radical, Organic Chemistry, General Chemistry, Frequency dependence, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, [CHIM.COOR]Chemical Sciences/Coordination chemistry
Abstract: Employing nitronyl nitroxide lanthanide(III) com- plexes as metallo-ligands allowed the efficient and highly se- lective preparation of three series of unprecedented hetero- tri-spin (CuLn-radical) one-dimensional compounds. These 2p-3d-4f spin systems, namely (Ln3Cu(hfac)11(NitPhOAll)4) (Ln III = Gd 1Gd ,T b1Tb ,D y1Dy; NitPhOAll = 2-(4'-allyloxyphen- yl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide), (Ln3Cu- (hfac)11(NitPhOPr)4 )( Ln III = Gd 2Gd ,T b2Tb ,D y2Dy ,H o2Ho ,Y b 2Yb; NitPhOPr = 2-(4'-propoxyphenyl)-4,4,5,5-tetramethyl-imi- dazoline-1-oxyl-3-oxide) and (Ln3Cu(hfac)11(NitPhOBz)4) (Ln III = Gd 3Gd ,T b3Tb ,D y3Dy; NitPhOBz = 2-(4'-benzyloxy- phenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide) in- volve O-bound nitronyl nitroxide radicals as bridging ligands in chain structures with a (Cu-Nit-Ln-Nit-Ln-Nit-Ln-Nit) re- peating unit. The dc magnetic studies show that ferromag- netic metal-radical interactions take place in these hetero- tri-spin chain complexes, these and the next-neighbor inter- actions have been quantified for the Gd derivatives. Com- plexes 1Tb and 2Tb exhibit frequency dependence of ac mag- netic susceptibilities, indicating single-chain magnet behav- ior.
Published: 2014

21. Catalytic Functionalization of Methane and Light Alkanes in Supercritical Carbon Dioxide

Author: Andrea Olmos, M. Ángeles Fuentes, M. Elena González‐Núñez, Ana Caballero, Pedro J. Pérez, Bianca K. Muñoz, Gregorio Asensio, Michel Etienne, Kane Jacob, Rossella Mello, Laboratorio de Catalisis Homogenea, Unidad Asociada al CSIC CIQSO-Centro de Investigacion en Quimica Sostenible and Departamento de Quimica, Universidad de Huelva, Universidad de Huelva, Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Departamento de Quimica Organica, Facultad de Farmacia, Universitat de Valencia, and Universitat de València (UV)
Subjects: Silver, Ligands, 010402 general chemistry, 01 natural sciences, 7. Clean energy, Catalysis, chemistry.chemical_compound, Ethyl propionate, Ethyl diazoacetate, Coordination Complexes, Methyl bisulfate, Alkanes, Organic chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Supercritical carbon dioxide, 010405 organic chemistry, Organic Chemistry, Butane, Diazonium Compounds, General Chemistry, Carbon Dioxide, 0104 chemical sciences, Solubility, chemistry, Isobutane, Oxidative coupling of methane, Methane
Abstract: International audience; The development of catalytic methods for the effective functionalization of methane yet remains a challenge. The best system known to date is the so-called Catalytica Process based on the use of platinum catalysts to convert methane into methyl bisulfate with a TOF rate of 10−3 s. In this contribution, we report a series of silver complexes containing perfluorinated tris(indazolyl)borate ligands that catalyze the functionalization of methane into ethyl propionate upon reaction with ethyl diazoacetate (EDA) by using supercritical carbon dioxide (scCO2) as the reaction medium. The employment of this reaction medium has also allowed the functionalization of ethane, propane, butane, and isobutane.
Published: 2014

22. Characterization of New Specific Copper Chelators as Potential Drugs for the Treatment of Alzheimer’s Disease

Author: Laure Vendier, Michel Nguyen, Anne Robert, Alix Sournia-Saquet, Bernard Meunier, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Chemical Engineering, Guangdong University of Technology, and Guangdong University of Technology
Subjects: inorganic chemicals, Amyloid, Metal ions in aqueous solution, Inorganic chemistry, Molecular Conformation, chemistry.chemical_element, Oxidative phosphorylation, Zinc, Crystallography, X-Ray, Medicinal chemistry, Catalysis, Drug Stability, Alzheimer Disease, Coordination Complexes, medicine, Humans, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Chelation, Electrodes, Serum Albumin, Chelating Agents, Amyloid beta-Peptides, Chemistry, Ligand, Organic Chemistry, Electrochemical Techniques, Hydrogen Peroxide, General Chemistry, Human serum albumin, Copper, Kinetics, Aminoquinolines, Oxidation-Reduction, Protein Binding, medicine.drug
Abstract: International audience; The non-controlled redox-active metal ions, especially copper, in the brain of patients with Alzheimer disease (AD) should be considered at the origin of the intense oxidative damage in the AD brain. Several bis(8-aminoquinoline) ligands, such as 1 and PA1637, are able to chelate Cu2+ with high affinity, and are specific chelators of copper with respect to iron and zinc. They are able to efficiently extract Cu2+ from a metal-loaded amyloid. In addition, these tetradentate ligands are specific for the chelation of Cu2+ compared with Cu+. Consequently, the copper ion is easily released from the bis(8-aminoquinoline) ligand under reductive conditions, and can be trapped again by a protein having some affinity for copper such as human serum albumin (HSA) proteins. In addition, the copper is not efficiently released from [Cu(CQ)2] in reductive conditions. The catalytic production of H2O2 by [Cu2+-Aβ1−28]/ascorbate is inhibited in vitro by the bis(8-aminoquinoline) 1, suggesting that 1 should be able to play a protective role against oxidative damages induced by copper-loaded amyloids.
Published: 2014

23. A Direct, Modular, and Efficient Construction of the PCP Structural Motif through Coupling of Manganese Carbyne Complexes with Phosphines

Author: Stéphanie Bastin, Dmitry A. Valyaev, Guy Lavigne, Kamil I. Utegenov, Nikolai A. Ustynyuk, Noël Lugan, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), A. N. Nesmeyanov Institute of Organoelement Compounds (INEOS), and Russian Academy of Sciences [Moscow] (RAS)
Subjects: Organic Chemistry, chemistry.chemical_element, Carbyne, General Chemistry, Manganese, Photochemistry, Catalysis, 3. Good health, Coupling (electronics), chemistry.chemical_compound, chemistry, Diphosphines, Polymer chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Structural motif
Abstract: 0947-6539; Easily available carbyne complexes of manganese were used as a source of carbyne fragments in an unconventional synthesis of backbone-substituted diphosphinomethanes and cyclic P-ylides upon coupling with secondary or tertiary phosphines, respectively, followed by demetalation under mild conditions.
Published: 2014

24. Surface Chemistry on Small Ruthenium Nanoparticles: Evidence for Site Selective Reactions and Influence of Ligands

Author: Pierre Lecante, Daniele M. Monahan, Guillermo Antorrena, Karine Philippot, Bruno Chaudret, Yannick Coppel, Fernando Novio, Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Laboratorio de microscopias avanzadas (LMA), University of Zaragoza - Universidad de Zaragoza [Zaragoza], Centre d'élaboration de matériaux et d'études structurales (CEMES), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Surfaces, Interfaces et Nano-Objets (CEMES-SINanO), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Laboratoire de physique et chimie des nano-objets (LPCNO), Université de Toulouse (UT)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratorio de Microscopias Avanzadas, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut National Polytechnique [Toulouse] (INP)-Université Toulouse III - Paul Sabatier (UPS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UPS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UPS)
Subjects: Steric effects, Chemistry, Ligand, Organic Chemistry, chemistry.chemical_element, surface chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, General Chemistry, solid‐state reactions, Photochemistry, Ethylbenzene, Catalysis, Reversible reaction, 3. Good health, Styrene, Ruthenium, chemistry.chemical_compound, [CHIM]Chemical Sciences, nanoparticles, Reactivity (chemistry), solid-state reactions, ruthenium
Abstract: International audience; The reactivity of two classes of ruthenium nanoparticles (Ru NPs) of small size, either sterically stabilized by a polymer (polyvinylpyrrolidone, PVP) or electronically stabilized by a ligand (bisdiphenylphosphinobutane, dppb) was tested towards standard reactions, namely CO oxidation, CO2 reduction and styrene hydrogenation. The aim of the work was to identify the sites of reactivity on the nanoparticles and to study how the presence of ancillary ligands can influence the course of these catalytic reactions by using NMR and IR spectroscopies. It was found that CO oxidation proceeds at room temperature (RT) on Ru NPs but that the system deactivates rapidly in the absence of ligands because of the formation of RuO2. In the presence of ligands, the reaction involves exclusively the bridging CO groups and no bulk oxidation is observed at RT under catalytic conditions. The reverse reaction, CO2 reduction, is achieved at 120 °C in the presence of H2 and leads to CO, which coordinates exclusively in a bridging mode, hence evidencing the competition between hydrides and CO for coordination on Ru NPs. The effect of ligands localized on the surface is also evidenced in catalytic reactions. Thus, styrene is slowly hydrogenated at RT by the two systems Ru/PVP and Ru/dppb, first into ethylbenzene and then into ethylcyclohexane. Selectively poisoning the nanoparticles with bridging CO groups leads to catalysts that are only able to reduce the vinyl group of styrene whereas a full poisoning with both terminal and bridging CO groups leads to inactive catalysts. These results are interpreted in terms of location of the ligands on the particles surface, and evidence site selectivity for both CO oxidation and arene hydrogenation.
Published: 2014

25. Chemical Behaviour of a Prototype Boryl(phosphino)carbene

Author: Eddy Maerten, Gilles Alcaraz, Florie Lavigne, Nathalie Saffon-Merceron, Antoine Baceiredo, Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Laboratoire de chimie de coordination (LCC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), and Université de Toulouse (UT)
Subjects: Bicyclic molecule, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Stereochemistry, Transition metal carbene complex, Organic Chemistry, General Chemistry, Nuclear magnetic resonance spectroscopy, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, Catalysis, Cycloaddition, 0104 chemical sciences, 3. Good health, chemistry.chemical_compound, chemistry, Intramolecular force, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Reactivity (chemistry), Singlet state, Carbene
Abstract: International audience; We recently disclosed the synthesis of a novel "push-pull" boryl(phosphino)carbene. To determine the influence of this substitution pattern on the chemical behaviour, a study into the reactivity of the prototype (1) of this new family of B(sp 2)-substituted phosphinocarbenes was undertaken. Carbene 1 exhibits one of the most common intramolecular rearrangements of singlet carbenes, involving a 1,2-mesityl shift, and typical [2+1] cycloaddition reactions with electron-poor acrylonitrile. A pronounced a,b-ambiphilic character was also shown by the reaction of 1 with benzaldehyde, leading to phosphorylalkene 4. Due to its specific electronic properties, carbene 1 also exhibits unprecedented reactivity with chloroacrylonitrile, enabling the formation of bicyclo[1.1.0]phosphetanium salt 6 and borylcyclopropene 9, which have been fully characterised by NMR spectroscopy and X-ray crystallography.
Published: 2013

26. Speciation of [Cp*2M2O5] in Polar and Donor Solvents

Author: Funda Demirhan, Agustí Lledós, Rinaldo Poli, Eric Manoury, Iker del Rosal, Pelin Sözen-Aktaş, Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, Faculty of Sciences & Liberal Arts, Celal Bayar University, Manisa Celal Bayar University, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Universitat Autònoma de Barcelona (UAB), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Speciation, Inorganic chemistry, DFT calculations, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, Tungsten, Catalysis, chemistry.chemical_compound, Solvent effects, Acetone, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Pentamethylcyclopentadienyl, Acetonitrile, Molybdenum, 010405 organic chemistry, Dimethyl sulfoxide, Organic Chemistry, General Chemistry, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Solvent, Density functional calculations, chemistry, Yield (chemistry), Proton NMR, Methanol
Abstract: The speciation of compounds [Cp*2 M2 O5 ] (M=Mo, W; Cp*=pentamethylcyclopentadienyl) in different protic and aprotic polar solvents (methanol, dimethyl sulfoxide, acetone, acetonitrile), in the presence of variable amounts of water or acid/base, has been investigated by (1) H NMR spectrometry and electrical conductivity. Specific hypotheses suggested by the experimental results have been further probed by DFT calculations. The solvent (S)-assisted ionic dissociation to generate [Cp*MO2 (S)](+) and [Cp*MO3 ](-) takes place extensively for both metals only in water/methanol mixtures. Equilibrium amounts of the neutral hydroxido species [Cp*MO2 (OH)] are generated in the presence of water, with the relative amount increasing in the order MeCN≈acetone
Published: 2013

27. Key Role of Intramolecular Metal Chelation and Hydrogen Bonding in the Cobalt-Mediated Radical Polymerization ofN-Vinyl Amides

Author: Rinaldo Poli, Yasmine Piette, Anthony Kermagoret, Antoine Debuigne, Christine Jérôme, Christophe Detrembleur, Aurélie N. Morin, Université de Liège, Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nitroxide mediated radical polymerization, Radical polymerization, macromolecular substances, 010402 general chemistry, Photochemistry, 01 natural sciences, Catalysis, Polymerization, Hydrogen bonds, Living free-radical polymerization, Chain-growth polymerization, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Reversible addition−fragmentation chain-transfer polymerization, Radical reactions, 010405 organic chemistry, Chemistry, Organic Chemistry, technology, industry, and agriculture, Chain transfer, Cobalt, [CHIM.CATA]Chemical Sciences/Catalysis, General Chemistry, 0104 chemical sciences, [CHIM.POLY]Chemical Sciences/Polymers, Cobalt-mediated radical polymerization, Chelates
Abstract: International audience; This work reveals the preponderance of an intramolecular metal chelation phenomenon in a controlled radical polymerization system involving the reversible trapping of the radical chains by a cobalt complex bis(acetylacetonato)cobalt(II). The cobalt‐mediated radical polymerization (CMRP) of a series of N‐vinyl amides was considered with the aim of studying the effect of the cobalt chelation by the amide moiety of the last monomer unit of the chain. The latter reinforces the cobalt-polymer bond in the order N‐vinylpyrrolidone
Published: 2012

28. Synthesis of Spin-Crossover Nano- and Micro-objects in Homogeneous Media

Author: Il'ya A. Gural'skiy, Igor O. Fritsky, Azzedine Bousseksou, Carlos M. Quintero, Lionel Salmon, Gábor Molnár, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry [Kyiv], and Taras Shevchenko National University of Kyiv
Subjects: Spin transition, Nanoparticle, Nanotechnology, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Catalysis, iron, spin crossover, Dynamic light scattering, Spin crossover, Nano, [CHIM.COOR]Chemical Sciences/Coordination chemistry, triazoles, polymers, chemistry.chemical_classification, Transition temperature, Organic Chemistry, General Chemistry, Polymer, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Chemical engineering, chemistry, nanoparticles, Nanorod, 0210 nano-technology
Abstract: International audience; New methods are proposed for the synthesis of spin‐crossover nano‐ and micro‐objects. Several nano‐objects that are based upon the spin‐crossover complex [Fe(hptrz)3](OTs)2 (hptrz=4‐heptyl‐1,2,4‐triazole, Ts=para‐toluenesulfonyl) were prepared in homogeneous media. The use of various reagents (Triton X‐100, PVP, TOPO, and PEGs of different molecular weights) as stabilizing agents yielded materials of different size (6 nm–2 μm) and morphology (nanorods, nanoplates, small spherical particles, and nano‐ and micro‐crystals). In particular, when Triton X‐100 was used, a variation in the morphology from nanorods to nanoplates was observed by changing the nature of the solvent. Interestingly, the preparation of the nanorods and nanoplates was always accompanied by the formation of small spherical particles. Alternatively, when PEG was used, 200–400 nm crystals of the complex were obtained. In addition, a very promising polymer‐free synthetic method is discussed that was based on the preparation of relatively stable FeII–triazole oligomers in CHCl3. Their specific treatment led to micro‐crystals, small nanoparticles, or gels. The size and morphology of all of these objects were characterized by TEM and by dynamic light scattering (DLS) where possible. Their spin‐crossover behavior was studied by optical and magnetic measurements. The spin‐transition features for large particles (>100 nm) were very similar to that of the bulk material, that is, close to room temperature with a hysteresis width of up to 8 K. The effects of the matrix and/or size‐reduction led to modification of the transition temperature and an abruptness of the spin transition for oligomeric solutions and small nanoparticles of 6 nm in size.
Published: 2012

29. Interplay between Cationic and Neutral Species in the Rhodium-Catalyzed Hydroaminomethylation Reaction

Author: Aitor Gual, David McKay, Philippe Kalck, Laurent Maron, Cyril Godard, Chiara Dinoi, Martine Urrutigoïty, Delphine Crozet, Jean-Claude Daran, Carmen Claver, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Departament de Química Física i Inorganica, Universitat Rovira i Virgili, Universitat Rovira i Virgili, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010405 organic chemistry, Organic Chemistry, Inorganic chemistry, Cationic polymerization, Infrared spectroscopy, chemistry.chemical_element, General Chemistry, Nuclear magnetic resonance spectroscopy, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, Oxidative addition, hydroaminomethylation, Catalysis, 0104 chemical sciences, Rhodium, NMR spectroscopy, Deprotonation, chemistry, density functional calculations, rhodium, coordination chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Reactivity (chemistry), Amine gas treating
Abstract: International audience; The reactivity of [Rh(CO)2{(R,R )‐PhBPE}]BF4 (2 ) toward amine, CO and/or H2 was examined by high‐pressure NMR and IR spectroscopy. The two cationic pentacoordinated species [Rh(CO)3{(R,R )‐PhBPE}]BF4 (4 ) and [Rh(CO)2(NHC5H10){(R,R )‐Ph‐BPE}]BF4 (8 ) were identified. The transformation of 2 into the neutral complex [RhH(CO)2{(R,R )‐PhBPE}] (3 ) under hydroaminomethylation conditions (CO/H2, amine) was investigated. The full mechanisms related to the formation of 3 , 4 and 8 starting from 2 are supported by DFT calculations. In particular, the pathway from 2 to 3 revealed the deprotonation by the amine of the dihydride species [Rh(H)2(CO)2{(R,R )‐PhBPE}]BF4 (6 ), resulting from the oxidative addition of H2 on 2 .
Published: 2012

30. Synthesis of 2‐ and 2,7‐Functionalized Pyrene Derivatives: An Application of Selective CH Borylation

Author: I.A. Mkhalid, Andrei S. Batsanov, Andrew G. Crawford, Judith A. K. Howard, Todd B. Marder, Marie-Hélène Thibault, Andreas Steffen, Jonathan C. Collings, Zhiqiang Liu, Gilles Alcaraz, Nicolle Schwarz, Durham University, Shandong University, King Abdulaziz University, Université Laval [Québec] (ULaval), Leibniz-Institut für Katalyse (LIKAT Rostock), Universität Rostock-Leibniz Association, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: crosscoupling, 010405 organic chemistry, Chemistry, Organic Chemistry, polycyclic aromatic, General Chemistry, sensors, 010402 general chemistry, 01 natural sciences, Borylation, Fluorescence, Catalysis, 0104 chemical sciences, chemistry.chemical_compound, Organic chemistry, Pyrene, [CHIM.COOR]Chemical Sciences/Coordination chemistry, fluorescence, C-H activation
Abstract: An efficient synthetic route to 2- and 2,7-substituted pyrenes is described. The regiospecific direct C-H borylation of pyrene with an iridium-based catalyst, prepared in situ by the reaction of [{Ir(μ-OMe)cod}(2)] (cod = 1,5-cyclooctadiene) with 4,4'-di-tert-butyl-2,2'-bipyridine, gives 2,7-bis(Bpin)pyrene (1) and 2-(Bpin)pyrene (2, pin = OCMe(2)CMe(2)O). From 1, by simple derivatization strategies, we synthesized 2,7-bis(R)-pyrenes with R = BF(3)K (3), Br (4), OH (5), B(OH)(2) (6), and OTf (7). Using these nominally nucleophilic and electrophilic derivatives as coupling partners in Suzuki-Miyaura, Sonogashira, and Buchwald-Hartwig cross-coupling reactions, we obtained 2,7-bis(R)-pyrenes with R = (4-CO(2)C(8)H(17))C(6)H(4) (8), Ph (9), C≡CPh (10), C≡C[{4-B(Mes)(2)}C(6)H(4)] (11), C≡CTMS (12), C≡C[(4-NMe(2))C(6)H(4)] (14), C≡CH (15), N(Ph)[(4-OMe)C(6)H(4)] (16), and R = OTf, R' = C≡CTMS (13). Lithiation of 4, followed by reaction with CO(2), yielded pyrene-2,7-dicarboxylic acid (17), whilst borylation of 2-tBu-pyrene gave 2-tBu-7-Bpin-pyrene (18) selectively. By similar routes (including Negishi cross-coupling reactions), monosubstituted 2-R-pyrenes with R = BF(3)K (19), Br (20), OH (21), B(OH)(2) (22), [4-B(Mes)(2)]C(6)H(4) (23), B(Mes)(2) (24), OTf (25), C≡CPh (26), C≡CTMS (27), (4-CO(2)Me)C(6)H(4) (28), C≡CH (29), C(3)H(6)CO(2)Me (30), OC(3)H(6)CO(2)Me (31), C(3)H(6)CO(2)H (32), OC(3)H(6)CO(2)H (33), and O(CH(2))(12)Br (34) were obtained from 2. These derivatives are of synthetic and photophysical interest because they contain donor, acceptor, and conjugated substituents. The crystal structures of compounds 4, 5, 7, 12, 18, 19, 21, 23, 26, and 28-31 have also been obtained from single-crystal X-ray diffraction data, revealing a diversity of packing modes, which are described in the Supporting Information. A detailed discussion of the structures of 1 and 2, their polymorphs, solvates, and co-crystals is reported separately.
Published: 2012

31. Pentacoordinate NiII Complexes

Author: Jean-Pierre Costes, Rémi Maurice, Laure Vendier, Zernike Institute for Advanced Materials, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Universitat Rovira i Virgili, Systèmes étendus et magnétisme (LCPQ) (SEM), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)
Subjects: inorganic chemicals, tridentate ligands, VALENCE, chemistry.chemical_element, Crystal structure, 010402 general chemistry, 01 natural sciences, NEUTRON-SCATTERING SPECTRA, Catalysis, NICKEL(II) COMPLEXES, nickel, ENERGY-LEVELS, O ligands, Computational chemistry, Ab initio quantum chemistry methods, otorhinolaryngologic diseases, IMPLEMENTATION, [CHIM]Chemical Sciences, Chelation, CRYSTAL-STRUCTURE, Anisotropy, Valence (chemistry), 010405 organic chemistry, ab initio calculations, STATE PERTURBATION-THEORY, Organic Chemistry, Hexacoordinate, General Chemistry, 0104 chemical sciences, Nickel, Magnetic anisotropy, Crystallography, chemistry, Condensed Matter::Strongly Correlated Electrons, magnetic properties, LIGAND, CLUSTERS, ZERO-FIELD SPLITTINGS
Abstract: Two novel mononuclear five- coordinate nickel complexes with dis- torted square-pyramidal geometries are presented. They result from association of a tridentate "half-unit" ligand and 6,6'-dimethyl-2,2'-bipyridine according to a stepwise process that highlights the advantage of coordination chemis- try in isolating an unstable tridentate ligand by nickel chelation. Their zero- field splittings (ZFS) were studied by means of magnetic data and state-of- the-art ab initio calculations. Good agreement between the experimental and theoretical axial D parameters confirms that large single-ion nickel anisotropies are accessible. The syn- thetic process can also yield dinuclear nickel complexes in which the nickel ions are hexacoordinate. This possibili- ty is facilitated by the presence of phe- noxo oxygen atoms in the tridentate ligand that can introduce a bridge be- tween the two nickel ions. Two differ- ent double bridges are characterized, with the bridging oxygen atoms coming from each nickel ion or from the same nickel ion. This coordination change in- troduces a difference in the antiferro- magnetic interaction parameter J.A l- though the magnetic data confirm the presence of single-ion anisotropies in these complexes, these terms cannot be determined in a straightforward way from experiment due to the mismatch between the principal axes of the local anisotropies and the presence of inter- site anisotropies.
Published: 2012

32. Reevaluation of Copper(I) Affinity for Amyloid-β Peptides by Competition with Ferrozine-An Unusual Copper(I) Indicator

Author: Bruno Alies, Bertrand Badei, Christelle Hureau, Peter Faller, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées
Subjects: Magnetic Resonance Spectroscopy, Stereochemistry, chemistry.chemical_element, Ferrozine, Peptide, 010402 general chemistry, Binding, Competitive, 01 natural sciences, Catalysis, Dithiothreitol, chemistry.chemical_compound, binding affinity, chromophores, Humans, Bicinchoninic acid assay, [CHIM.COOR]Chemical Sciences/Coordination chemistry, chemistry.chemical_classification, Amyloid beta-Peptides, Molecular Structure, 010405 organic chemistry, Organic Chemistry, General Chemistry, Nuclear magnetic resonance spectroscopy, Chromophore, Ligand (biochemistry), Copper, 0104 chemical sciences, chemistry, amyloid-beta peptides, Indicators and Reagents, Titration
Abstract: The association constant of ferrozine (5,6-diphenyl-3-(2-pyridyl)-1,2,4-triazine-4,4''-disulfonic acid) with Cu(I) to form the chromophoric [Cu(I)(Fz)(2)](3-) complex was determined by UV/Vis titration experiments in Hepes buffer (0.1 M, pH 7.4). An association constant close to 10(12) M(-2), which is significantly weaker than those of the well-known, water-soluble, Cu(I) chelators bicinchoninic acid and 2,9-dimethyl-4,7-diphenyl-1,10-phenantroline disulfonic acid, was found. The [Cu(I)(Fz)(2)](3-) chromophore was used in UV/Vis competition experiments to determine Cu(I) binding affinity for the amyloid-β peptide involved in Alzheimer's disease and for a series of pertinent mutants. An association constant of approximately 10(7) M(-1) was found; this is much weaker than that reported for dithiothreitol and confirms that imidazoles are harder ligands than thiolates. Each His mutation (H6A, H13A, and H14A) impacts the peptide affinity for Cu(I). The native human amyloid-β peptide was found to be a fourfold-stronger Cu(I) ligand than the murine peptide, which differs by three point mutations (R5G, Y10F, and H13R) from the human one.
Published: 2011

33. Towards the Limit of Atropochiral Stability: H-MIOP, an N-Heterocyclic Carbene Precursor and Cationic Analogue of the H-MOP Ligand

Author: Ibrahim Abdellah, Remi Chauvin, Christine Lepetit, Martial Boggio-Pasqua, Yves Canac, Carine Duhayon, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Chimie des éléments d & f (LCPQ), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: Steric effects, Benzimidazole, 010405 organic chemistry, Chemistry, Ligand, Stereochemistry, Organic Chemistry, Cationic polymerization, General Chemistry, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, Catalysis, 0104 chemical sciences, chemistry.chemical_compound, [CHIM.OTHE]Chemical Sciences/Other, Acetonitrile, Racemization, Carbene, Bond cleavage
Abstract: International audience; The configurational stability of biaryl motifs is addressed for the 1-naphthyl-N-benzimidazolyl motif substituted by a single diphenylphosphinyl group at the 2-position. The atropoenantiomers of the N-methylated cation H-MIOP, a less sterically locked analogue of the neutral H-MOP ligand, were resolved by enantiospecific cleavage of the N(2)C-P bond of the resolved enantiomers of BIMIONAP. The latter were obtained by enantiospecific N-methylation of the previously resolved enantiomers of neutral BIMINAP. PdCl(2) complexes of the P,C-chelating N-heterocyclic carbene (NHC)-phosphine ligands derived from (R)- and (S)-H-MIOP were prepared by two enantiospecific routes: by N(2)C-P bond cleavage from the (R)- and (S)-BIMIONAP-PdCl(2) complexes, or by simultaneous coordination of the P and C atoms of the in situ generated free NHC-phosphine. The enantiomerization pathways of H-MOP, H-MIOP, and corresponding NHC-phosphine have been investigated at the B3PW91/6-31G(d,p) level of theory. The calculated enantiomerization barriers of H-MOP and H-MIOP in acetonitrile are equal to 176.0 and 146.4 kJ mol(-1), respectively, and are mainly determined by the distortion of the naphthalene and/or benzimidazole motifs in the transition state. Beyond the stability of their optical rotation at room temperature, the respective calculated Oki's racemization temperatures of 334 and 225 °C allowed us to consider both ligands as configurationally stable.
Published: 2011

34. Three‐Dimensional Open‐Frameworks Based on LnIIIIons and Open‐/Closed‐Shell PTM Ligands: Synthesis, Structure, Luminescence, and Magnetic Properties

Author: Angela Datcu, Nans Roques, Véronique Jubera, Daniel Maspoch, Inhar Imaz, Jean-Pascal Sutter, Jaume Veciana, Concepció Rovira, European Commission, Ministerio de Ciencia e Innovación (España), Instituto de Salud Carlos III, Generalitat de Catalunya, Comunidad de Trabajo de los Pirineos, Institut de Ciència de Materials de Barcelona (ICMAB), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Université de Bordeaux (UB), Centre d'Investigació en Nanociència i Nanotecnologia (ICN-CSIC), and Universitat Autònoma de Barcelona (UAB)
Subjects: Models, Molecular, Lanthanide, Luminescence, Photoluminescence, Inorganic chemistry, Molecular Conformation, Crystallography, X-Ray, Ligands, 010402 general chemistry, Lanthanoid Series Elements, 01 natural sciences, Tricarboxylate, Catalysis, Magnetics, X-Ray Diffraction, Lanthanides, Magnetic properties, Antiferromagnetism, Polychloroterphenyl Compounds, Isostructural, Ions, Metal–organic frameworks, Molecular Structure, 010405 organic chemistry, Ligand, Chemistry, Organic Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, Radicals, General Chemistry, 0104 chemical sciences, 3. Good health, Crystallography, Metals, Metal-organic framework
Abstract: 13 páginas, 12 figuras, 2 tablas.-- et al., A series of isostructural open-framework coordination polymers formulated as [Ln(dmf)3(ptmtc)] (Ln=Sm (1), Eu (2), Gd (3), Tb (4), Dy (5); PTMTC=polychlorotriphenylmethyl tricarboxylate) and [Ln(dmf)2H2O(αH-ptmtc)] (Ln=Sm (1′), Eu (2′), Gd (3′), Tb (4′), Dy (5′)) have been obtained by treating LnIII ions with PTMTC ligands with a radical (PTMTC3−) or a closed-shell character (αH-PTMTC3−). X-ray diffraction analyses reveal that these coordination polymers possess 3D architectures that combine large channels and fairly rare lattice complex T connectivity. In addition, these compounds show selective framework dynamic sorption properties. For both classes of ligands, the ability to act as an antenna in Ln sensitization processes has been investigated. No luminescence was observed for compounds 1–5, and 3′ because of the PTMTC3− ligand and/or GdIII ion characteristics. Conversely, photoluminescence measurements show that 1′, 2′, 4′, and 5′ emit dark orange, red, green, and dark cyan metal-centered luminescence. The magnetic properties of all of these compounds have been investigated. The nature of the {Ln–radical} exchange interaction in these compounds has been assessed by comparing the behavior of the radical-based coordination polymers 1–5 with those of the compounds with the diamagnetic ligand set. While antiferromagnetic {Sm–radical} interactions are found in 1, ferromagnetic {Ln–radical} interactions propagate in the 3D architectures of 3, 4, and 5 (Ln=Gd, Tb, and Dy, respectively). This procedure also provided access to information on the {Ln Ln} exchange existing in these magnetic systems., We thank the EU, under contract MAGMANet (no. 515767) of 6th FP, the Instituto de Salud Carlos III through “Acciones CIBER’’, the MICINN, Spain (CTQ2006-06333/BQU and CTQ2010-19501/BQU), Generalitat de Catalunya (2009SGR00516), and the Région Midi-Pyrénées in the frame of the Communauté de Travail des Pyrénées (CTP, program 2007) for funding.
Published: 2011

35. Olefin Epoxidation by H2O2/MeCN Catalysed by Cyclopentadienyloxidotungsten(VI) and Molybdenum(VI) Complexes: Experiments and Computations

Author: Laurent Maron, Chiara Dinoi, Eric Manoury, Lionel Perrin, Marco Ciclosi, Rinaldo Poli, Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), and Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Inorganic chemistry, Epoxidation, 010402 general chemistry, 7. Clean energy, 01 natural sciences, Medicinal chemistry, Tungsten, Catalysis, chemistry.chemical_compound, Nucleophile, Cyclooctene, Acetonitrile, Molybdenum, Olefin fiber, Aqueous solution, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Organic Chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, General Chemistry, Hydrogen peroxide, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Density functional calculations, chemistry, Diethyl ether, Natural bond orbital
Abstract: Compounds [Cp*(2)M(2)O(5)] (M = Mo, 1; W, 2) are efficient pre-catalysts for cyclooctene (COE) epoxidation by aqueous H(2)O(2) in acetonitrile/toluene. The reaction is quantitative, selective and takes place approximately 50 times faster for the W system (k(obs) = 4.32(9)x10(-4) s(-1) at 55 degrees C and 3x10(-3) M concentration for the dinuclear complex, vs. 1.06(7)x10(-5) s(-1) for the Mo system). The rate law is first order in catalyst and COE substrate (k = 0.138(7) M(-1) s(-1) for the W system at 55 degrees C), whereas increasing the concentration of H(2)O(2) slows down the reaction because of an inhibiting effect of the greater amount of water. The activation parameters for the more active W systems (DeltaH(double dagger) = 10.2(6) kcal mol(-1); DeltaS(double dagger) = -32(2) cal mol(-1) K(-1)) were obtained from an Eyring study in the 25-55 degrees C temperature range. The H(2)O(2)urea adduct was less efficient as an oxidant than the aqueous H(2)O(2) solution. Replacement of toluene with diethyl ether did not significantly affect the catalyst efficiency, whereas replacement with THF slowed down the process. The epoxidation of ethylene as a model olefin, catalysed by the [Cp*MO(2)Cl] systems (M = W, Mo) in the presence of H(2)O(2) as oxidant and acetonitrile as solvent, has been investigated by DFT calculations with the use of the conductor-like polarisable continuum model (CPCM). For both metal systems, the rate-limiting step is the transfer of the hydroperoxido O(alpha) atom to the olefin, in accordance with the first-order dependence on the substrate and the zero-order dependence on H(2)O(2) found experimentally in the catalytic data. The activation barrier corresponding to the rate-limiting step is 4 kcal lower for the W complex than for the corresponding Mo analogue (32.3 vs. 28.3 kcal mol(-1)). This result reproduces well the higher catalytic activity of the W species. The different catalytic behaviour between the two systems is rationalised by a natural bond orbital (NBO) study and natural population analyses (NPA). Compared to Mo, the W(VI) centre withdraws more electron density from the sigma bonding [O-O] orbital and favours, as a consequence, the nucleophilic attack of the external olefin on the sigma*[O-O] orbital.
Published: 2010

36. Effect of the Nature of the Metal Atom on Hydrogen Bonding and Proton Transfer to [Cp*MH3(dppe)]: Tungsten versus Molybdenum

Author: Lina M. Epstein, Rinaldo Poli, Pavel A. Dub, Natalia V. Belkova, Agustí Lledós, Elena S. Shubina, Maria Besora, Miguel Baya, Pavel O. Revin, A. N. Nesmeyanov Institute of Organoelement Compounds (INEOS), Russian Academy of Sciences [Moscow] (RAS), Departament de Química [Barcelona] (UAB), Universitat Autònoma de Barcelona (UAB), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Models, Molecular, Hydrogen bonding, Proton, chemistry.chemical_element, Protonation, 010402 general chemistry, Photochemistry, 01 natural sciences, Tungsten, Proton transfer, Catalysis, Adduct, Metal, Hydrido complexes, Organometallic Compounds, Phosphine ligands, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Molybdenum, 010405 organic chemistry, Hydride, Hydrogen bond, Organic Chemistry, General Chemistry, 0104 chemical sciences, Crystallography, chemistry, visual_art, visual_art.visual_art_medium, Quantum Theory, Thermodynamics, Chemical stability, Protons
Abstract: The hydrogen-bonding and proton-transfer pathway to complex [Cp*W(dppe)H(3)] (Cp*=eta(5)-C(5)Me(5); dppe=Ph(2)PCH(2)CH(2)PPh(2)) was investigated experimentally by IR, NMR, UV/Vis spectroscopy in the presence of fluorinated alcohols, p-nitrophenol, and HBF(4), and by using DFT calculations for the [CpW(dhpe)H(3)] model (Cp=eta(5)-C(5)H(5); dhpe=H(2)PCH(2)CH(2)PH(2)) and for the real system. A study of the interaction with weak acids (CH(2)FCH(2)OH, CF(3)CH(2)OH, (CF(3))(2)CHOH) allowed the determination of the basicity factor, E(j)=1.73+/-0.01, making this compound the most basic hydride complex reported to date. A computational investigation revealed several minima for the [CpW(dhpe)H(3)] adducts with CF(3)CH(2)OH, (CF(3))(2)CHOH, and 2(CF(3))(2)CHOH and confirms that these interactions are stronger than those established by the Mo analogue. Their geometries and relative energies are closely related to those of the homologous Mo systems, with the most stable adducts corresponding to H bonding with M-H sites, however, the geometric and electronic parameters reveal that the metal center plays a greater role in the tungsten systems. Proton-transfer equilibria are observed with the weaker proton donors, the proton-transfer step for the system [Cp*W(dppe)H(3)]/HOCH(CF(3))(2) in toluene having DeltaH=(-3.9+/-0.3) kcal mol(-1) and DeltaS=(-17+/-2) cal mol(-1) K(-1). The thermodynamic stability of the proton-transfer product is greater for W than for Mo. Contrary to the Mo system, the protonation of the [Cp*W(dppe)H(3)] appears to involve a direct proton transfer to the metal center without a nonclassical intermediate, although assistance is provided by a hydride ligand in the transition state.
Published: 2008

37. First Dicyanamide-Bridged Spin-Crossover Coordination Polymer: Synthesis, Structural, Magnetic, and Spectroscopic Studies

Author: Serguei A. Borshch, Caroline Genre, Azzedine Bousseksou, Galina S. Matouzenko, Erwann Jeanneau, Dominique Luneau, Laboratoire de Chimie - UMR5182 (LC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Laboratoire des Multimatériaux et Interfaces (LMI), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Institut de Chimie de Toulouse (ICT), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Models, Molecular, Polymers, Coordination polymer, Stereochemistry, Iron, Spin transition, Cooperativity, Crystal structure, Triclinic crystal system, Crystallography, X-Ray, Ligands, Spectrum Analysis, Raman, 010402 general chemistry, 01 natural sciences, Catalysis, Magnetics, Spectroscopy, Mossbauer, chemistry.chemical_compound, Spin crossover, Ferrous Compounds, Dicyanamide, ComputingMilieux_MISCELLANEOUS, Molecular Structure, 010405 organic chemistry, Ligand, Organic Chemistry, Temperature, Hydrogen Bonding, General Chemistry, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Crystallography, chemistry, Cyanamide, Aminoquinolines, Quantum Theory
Abstract: We report here on the synthesis and characterisation of a first iron(II) spin-crossover coordination polymer with the dca spacer ligand, having the formula [Fe(aqin)2(dca)]ClO4.MeOH (aqin=8-aminoquinoline, dca=dicyanamide), which displays a two-step complete spin transition. Variable-temperature magnetic susceptibility measurements and Mössbauer spectroscopy have revealed that the two relatively gradual steps are centred at 215 and 186 K and are separated by an inflection point at about 201 K, at which 50 % of the complex molecules undergo a spin transition. The two steps are related to the existence of two crystallographically inequivalent metal sites, as confirmed by the structural and Mössbauer studies. The crystal structure was resolved at 293 K (HS form) and 130 K (LS form). Both spin-state structures belong to the triclinic P1 space group (Z=2). The complex assumes a linear chain structure, in which the active iron(II) sites are linked to each other by anionic dicyanamide ligands acting as chemical bridges. The Fe-Fe distances through the dca ligand are 8.119(1) and 7.835(1) A in the high-spin and low-spin structures, respectively. The polymeric chains extend along a (1, 0, -1) axis and are packed in sheets, between which the perchlorate anions and methanol molecules are inserted. The complex molecules are linked together by pi-stacking interactions and H-bonding between the H-donor aqin ligands and the perchlorate ions. These structural features provide a basis for cooperative interactions in the crystal lattice. Analysis of the two-step spin-crossover character in this compound suggests that covalent interactions through the spacer ligand do not provide the main mechanism of cooperativity.
Published: 2008

38. Synthesis of Novel Rod-Shaped and Star-Shaped Fluorescent Phosphane Oxides—Nonlinear Optical Properties and Photophysical Properties

Author: Vincent Souchon, Véronique Michelet, Jean-Pierre Genêt, Keitaro Nakatani, Isabelle Leray, Valérie Alain, Abdelwaheb Hamdi, Rémi Métivier, Pascal G. Lacroix, Minh-Huong Ha-Thi, Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL), École normale supérieure - Cachan (ENS Cachan)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT-FR 2599), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Synthèses sélective organique et produits naturels (SSOPN), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3)
Subjects: Nonlinear optics, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Organic Chemistry, Solvatochromism, Oxide, General Chemistry, Chromophore, Phosphane oxide, 010402 general chemistry, Photochemistry, 01 natural sciences, Fluorescence, Catalysis, Fluorescence spectroscopy, 0104 chemical sciences, chemistry.chemical_compound, Charge transfer, chemistry, Moiety, Molecule, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract: International audience; The design of a new class of fluorophores is presented. Some push– pull chromophores (D–p–A) containing polyphenylethynyl units and a phosphane oxide moiety were efficiently prepared from common intermediates. Straightforward syntheses gave novel one-armed, rod-shaped and three-armed, star-shaped fluorophores. The optical properties of the resulting star-shaped derivatives were evaluated, showed high fluorescence quantum yields, and their excitation induces very efficient charge redistribution. Moreover, thanks to their push–pull character, the molecules exhibited significant second-order NLO properties with good transparency, up to 67·1030 esu at 1907 nm, with an absorption lmax at 369 nm. The effect of the donor group and of the number of phenylethynyl arms have been studied in this work.
Published: 2006

39. Acrolein and Copper as Competitive Effectors of α‐Synuclein

Author: Petra Hellwig, Bertrand Vileno, Ikhlas Mohamed Mohamud Ahmed, Enrico Falcone, Peter Faller, Valentina Oliveri, Graziella Vecchio, Francesco Bellia, Youssef El Khoury, Institut de Chimie de Strasbourg, Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Centre National de la Recherche Scientifique (CNRS)-Université Louis Pasteur - Strasbourg I-Institut de Chimie du CNRS (INC), Laboratoire de Bioélectrochimie et Spectroscopie, Chimie de la matière complexe (CMC), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), University of Catania [Italy], Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: medicine.disease_cause, Acrolein, Aggregation, Oligomers, Synuclein, copper, 01 natural sciences, Protein Carbonylation, chemistry.chemical_compound, Tandem Mass Spectrometry, immune system diseases, [SDV.IMM.ALL]Life Sciences [q-bio]/Immunology/Allergology, skin and connective tissue diseases, Chromatography, High Pressure Liquid, ComputingMilieux_MISCELLANEOUS, chemistry.chemical_classification, Effector, amyloid beta-peptides, aggregation, [CHIM.MATE]Chemical Sciences/Material chemistry, [SDV.BBM.BP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biophysics, alpha-Synuclein, musculoskeletal diseases, inorganic chemicals, chemistry.chemical_element, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, Catalysis, Protein Aggregates, synuclein, medicine, Humans, oligomers, Reactive oxygen species, 010405 organic chemistry, Organic Chemistry, General Chemistry, Copper, Dynamic Light Scattering, nervous system diseases, 0104 chemical sciences, Oxidative Stress, nervous system, chemistry, Biophysics, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Reactive Oxygen Species, Carbonylation, Oxidative stress
Abstract: Mounting evidence supports the role of amyloidogenesis, oxidative stress, and metal dyshomeostasis in the development of neurodegenerative disorders. Parkinson's Disease is characterized by alpha-synuclein (alpha Syn) accumulation and aggregation in brain regions, also promoted by Cu2+. alpha Syn is modified by reactive carbonyl species, including acrolein (ACR). Notwithstanding these findings, the interplay between ACR, copper, and alpha Syn has never been investigated. Therefore, we explored more thoroughly the effects of ACR on alpha Syn using an approach based on LC-MS/MS analysis. We also evaluated the influence of Cu2+ on the protein carbonylation and how the ACR modification impacts the Cu2+ binding and the production of Reactive Oxygen Species (ROS). Finally, we investigated the effects of ACR and Cu2+ ions on the alpha Syn aggregation by dynamic light scattering and fluorescence assays. Cu2+ regioselectively inhibits the modification of His50 by ACR, the carbonylation lowers the affinity of His50 for Cu2+ and ACR inhibits alpha Syn aggregation both in the presence and in the absence of Cu2+.
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