Author: "Sébastien Blanchard" - Searchworks@Jio Institute Digital Library Search Results

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1. Mn-Doped Quinary Ag–In–Ga–Zn–S Quantum Dots for Dual-Modal Imaging

Author: Perizat Galiyeva, Hervé Rinnert, Sabine Bouguet-Bonnet, Sébastien Leclerc, Lavinia Balan, Halima Alem, Sébastien Blanchard, Jordane Jasniewski, Ghouti Medjahdi, Bolat Uralbekov, and Raphaël Schneider
Subjects: Chemistry, QD1-999
Published: 2021
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2. Highly Luminescent and Photostable Core/Shell/Shell ZnSeS/Cu:ZnS/ZnS Quantum Dots Prepared via a Mild Aqueous Route

Author: Salima Mabrouk, Hervé Rinnert, Lavinia Balan, Jordane Jasniewski, Sébastien Blanchard, Ghouti Medjahdi, Rafik Ben Chaabane, and Raphaël Schneider
Subjects: core/shell/shell ZnSeS/Cu:ZnS/ZnS quantum dots, dopant location, optoelectronic properties, (photo)stability, Chemistry, QD1-999
Abstract: An aqueous-phase synthesis of 3-mercaptopropionic acid (3-MPA)-capped core/shell/shell ZnSeS/Cu:ZnS/ZnS QDs was developed. The influence of the Cu-dopant location on the photoluminescence (PL) emission intensity was investigated, and the results show that the introduction of the Cu dopant in the first ZnS shell leads to QDs exhibiting the highest PL quantum yield (25%). The influence of the Cu-loading in the dots on the PL emission was also studied, and a shift from blue–green to green was observed with the increase of the Cu doping from 1.25 to 7.5%. ZnSeS/Cu:ZnS/ZnS QDs exhibit an average diameter of 2.1 ± 0.3 nm and are stable for weeks in aqueous solution. Moreover, the dots were found to be photostable under the continuous illumination of an Hg–Xe lamp and in the presence of oxygen, indicating their high potential for applications such as sensing or bio-imaging.
Published: 2022
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3. Optimizing Group Transfer Catalysis by Copper Complex with Redox-Active Ligand in an Entatic State

Author: Yufeng Ren, Jeremy Forté, Khaled Cheaib, Nicolas Vanthuyne, Louis Fensterbank, Hervé Vezin, Maylis Orio, Sébastien Blanchard, and Marine Desage-El Murr
Subjects: Science
Abstract: Summary: Metalloenzymes use earth-abundant non-noble metals to perform high-fidelity transformations in the biological world. To ensure chemical efficiency, metalloenzymes have acquired evolutionary reactivity-enhancing tools. Among these, the entatic state model states that a strongly distorted geometry induced by ligands around a metal center gives rise to an energized structure called entatic state, strongly improving the reactivity. However, the original definition refers both to the transfer of electrons or chemical groups, whereas the chemical application of this concept in synthetic systems has mostly focused on electron transfer, therefore eluding chemical transformations. Here we report that a highly strained redox-active ligand enables a copper complex to perform catalytic nitrogen- and carbon-group transfer in as fast as 2 min, thus exhibiting a strong increase in reactivity compared with its unstrained analogue. This report combines two reactivity-enhancing features from metalloenzymes, entasis and redox cofactors, applied to group-transfer catalysis. : Inorganic Chemistry; Molecular Inorganic Chemistry; Catalysis Subject Areas: Inorganic Chemistry, Molecular Inorganic Chemistry, Catalysis
Published: 2020
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4. New Caffeic Acid Phenylethyl Ester Analogs Bearing Substituted Triazole: Synthesis and Structure-Activity Relationship Study towards 5-Lipoxygenase Inhibition

Author: Pierre-Philipe Roy, Diene Faye, Sébastien Blanchard, Marc Cormier, Jérémie A. Doiron, Marc E. Surette, and Mohamed Touaibia
Subjects: Chemistry, QD1-999
Abstract: Leukotrienes are biosynthesized by the conversion of arachidonic acid by 5-Lipoxygenase and play a key role in many inflammatory disorders. Inspired by caffeic acid phenylethyl ester (CAPE) (2) and an analog carrying a triazole substituted by cinnamoyl and 5-LO inhibitors recently reported by our team, sixteen new CAPE analogs bearing substituted triazole were synthesized by copper catalyzed Huisgen 1,3-dipolar cycloaddition. Compound 10e, an analog bearing p-CF3 phenethyl substituted triazole, was equivalent to CAPE (2) but clearly surpassed Zileuton (2), the only approved 5-LO inhibitor. Substitution of the phenethyl moiety by cyclohexylethyl, as with 12g, clearly increased 5-LO inhibition which confirms the importance of hydrophobic interactions. Molecular docking revealed new hydrogen bonds and π-π interactions between the enzyme and some of the investigated compounds. Overall, this work highlights the relevance of exploring polyphenolic compounds as leukotrienes biosynthesis inhibitors.
Published: 2017
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5. New Hydroxycinnamic Acid Esters as Novel 5-Lipoxygenase Inhibitors That Affect Leukotriene Biosynthesis

Author: Luc H. Boudreau, Grégoire Lassalle-Claux, Marc Cormier, Sébastien Blanchard, Marco S. Doucet, Marc E. Surette, and Mohamed Touaibia
Subjects: Pathology, RB1-214
Abstract: Leukotrienes are inflammatory mediators that actively participate in the inflammatory response and host defense against pathogens. However, leukotrienes also participate in chronic inflammatory diseases. 5-lipoxygenase is a key enzyme in the biosynthesis of leukotrienes and is thus a validated therapeutic target. As of today, zileuton remains the only clinically approved 5-lipoxygenase inhibitor; however, its use has been limited due to severe side effects in some patients. Hence, the search for a better 5-lipoxygenase inhibitor continues. In this study, we investigated structural analogues of caffeic acid phenethyl ester, a naturally-occurring 5-lipoxygenase inhibitor, in an attempt to enhance the inhibitory activity against 5-lipoxygenase and determine structure-activity relationships. These compounds were investigated for their ability to attenuate the biosynthesis of leukotrienes. Compounds 13 and 19, phenpropyl and diphenylethyl esters, exhibited significantly enhanced inhibitory activity when compared to the reference molecules caffeic acid phenethyl ester and zileuton.
Published: 2017
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6. Structure–Activity Relationship Studies of New Sinapic Acid Phenethyl Ester Analogues Targeting the Biosynthesis of 5-Lipoxygenase Products: The Role of Phenolic Moiety, Ester Function, and Bioisosterism

Author: Mohamed Touaibia, Diene Codou Faye, Jérémie A. Doiron, Audrey Isabel Chiasson, Sébastien Blanchard, Pierre-Philippe Roy, and Marc E. Surette
Subjects: Pharmacology, Arachidonate 5-Lipoxygenase, Coumaric Acids, Neutrophils, Organic Chemistry, Pharmaceutical Science, Esters, Phenylethyl Alcohol, Analytical Chemistry, Structure-Activity Relationship, HEK293 Cells, Complementary and alternative medicine, Drug Discovery, Humans, Molecular Medicine
Abstract: Sinapic acid is found in many edible plants and fruits, such as rapeseed, where it is the predominant phenolic compound. New sinapic acid phenethyl ester (SAPE) analogues were synthesized and screened as inhibitors of the biosynthesis of 5-lipoxygenase (5-LO) in stimulated HEK293 cells and polymorphonuclear leukocytes (PMNL). Inhibition of leukotriene biosynthesis catalyzed by 5-LO is a validated therapeutic strategy against certain inflammatory diseases and allergies. Unfortunately, the only inhibitor approved to date has limited clinical use because of its poor pharmacokinetic profile and liver toxicity. With the new analogues synthesized in this study, the role of the phenolic moiety, ester function, and bioisosterism was investigated. Several of the 34 compounds inhibited the biosynthesis of 5-LO products, and 20 compounds were 2-11 times more potent than zileuton in PMNL, which are important producers of 5-LO products. Compounds
Published: 2022
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7. Mn-Doped Quinary Ag–In–Ga–Zn–S Quantum Dots for Dual-Modal Imaging

Author: Raphaël Schneider, Bolat Uralbekov, Perizat Galiyeva, Jordane Jasniewski, Halima Alem, Sébastien Leclerc, Sébastien Blanchard, Hervé Rinnert, Ghouti Medjahdi, Sabine Bouguet-Bonnet, Lavinia Balan, Laboratoire Réactions et Génie des Procédés (LRGP), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institut Jean Lamour (IJL), Université de Lorraine (UL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Cristallographie, Résonance Magnétique et Modélisations (CRM2), Laboratoire Énergies et Mécanique Théorique et Appliquée (LEMTA ), Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université d'Orléans (UO), Institut Parisien de Chimie Moléculaire (IPCM), Chimie Moléculaire de Paris Centre (FR 2769), Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Ingénierie des Biomolécules (LIBio), Université de Lorraine (UL), Al-Farabi Kazakh National University [Almaty] (KazNU), IMPACT Biomolécules, and ANR-15-IDEX-0004,LUE,Isite LUE(2015)
Subjects: Materials science, General Chemical Engineering, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Article, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Condensed Matter::Materials Science, Semiconductor quantum dots, Transition metal, Condensed Matter::Superconductivity, Mn doped, QD1-999, business.industry, Doping, Quinary, General Chemistry, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Dual (category theory), [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Chemistry, Modal, Quantum dot, Optoelectronics, Condensed Matter::Strongly Correlated Electrons, 0210 nano-technology, business
Abstract: International audience; Doping of transition metals within a semiconductor quantum dot (QD) has a high impact on the optical and magnetic properties of the QD. In this study, we report the synthesis of Mn 2+-doped Ag−In−Ga−Zn−S (Mn:AIGZS) QDs via thermolysis of a dithiocarbamate complex of Ag + , In 3+ , Ga 3+ , and Zn 2+ and of Mn(stearate) 2 in oleylamine. The influence of the Mn 2+ loading on the photoluminescence (PL) and magnetic properties of the dots are investigated. Mn:AIGZS QDs exhibit a diameter of ca. 2 nm, a high PL quantum yield (up to 41.3% for a 2.5% doping in Mn 2+), and robust photo-and colloidal stabilities. The optical properties of Mn:AIGZS QDs are preserved upon transfer into water using the glutathione tetramethylammonium ligand. At the same time, Mn:AIGZS QDs exhibit high relaxivity (r 1 = 0.15 mM −1 s −1 and r 2 = 0.57 mM −1 s −1 at 298 K and 2.34 T), which shows their potential applicability for bimodal PL/magnetic resonance imaging (MRI) probes.
Published: 2021
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8. Interplay Between Hydrogen Bonding and Electron Transfer in Mixed Valence Assemblies of Triarylamine Trisamides

Author: Quentin Sallembien, Paméla Aoun, Sébastien Blanchard, Laurent Bouteiller, and Matthieu Raynal
Subjects: Organic Chemistry, General Chemistry, Catalysis
Abstract: Hydrogen-bonding interactions are assumed to play a critical role in the long-range transport of light or charge recently observed in supramolecular assemblies of C
Published: 2022
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9. Tuning Photoinduced Electron Transfer in POM‐Bodipy Hybrids by Controlling the Environment: Experiment and Theory

Author: Pavel Chábera, Albert Masip-Sánchez, Joshua K. G. Karlsson, Sandra Alves, Tõnu Pullerits, Ian P. Clark, Fiona Black, Georgios Toupalas, Sébastien Blanchard, Xavier López, Josep M. Poblet, Youssef Ben M'Barek, Guillaume Izzet, Anna Proust, Elizabeth A. Gibson, Institut Parisien de Chimie Moléculaire (IPCM), Chimie Moléculaire de Paris Centre (FR 2769), Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Newcastle University [Newcastle], and Universitat Rovira i Virgili
Subjects: chemistry.chemical_classification, Materials science, 010405 organic chemistry, General Chemistry, General Medicine, 010402 general chemistry, 01 natural sciences, Catalysis, Photoinduced electron transfer, Marcus theory, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, Molecular dynamics, Electron transfer, Solvation shell, chemistry, Chemical physics, Intramolecular force, Counterion, BODIPY, [CHIM.OTHE]Chemical Sciences/Other
Abstract: The optical and electrochemical properties of a series of polyoxometalate (POM) oxoclusters decorated with two bodipy (boron-dipyrromethene) light-harvesting units were examined. Evaluated here in this polyanionic donor-acceptor system is the effect of the solvent and associated counterions on the intramolecular photoinduced electron transfer. The results show that both solvents and counterions have a major impact upon the energy of the charge-transfer state by modifying the solvation shell around the POMs. This modification leads to a significantly shorter charge separation time in the case of smaller counterion and slower charge recombination in a less polar solvent. These results were rationalized in terms of Marcus theory and show that solvent and counterion both affect the driving force for photoinduced electron transfer and the reorganization energy. This was corroborated with theoretical investigations combining DFT and molecular dynamics simulations.
Published: 2021
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10. When Identification of the Reduction Sites in Mixed Molybdenum/Tungsten Keggin-Type Polyoxometalate Hybrids Turns Out Tricky

Author: Maxime Laurans, Michele Mattera, Raphaël Salles, Ludivine K’Bidi, Pierre Gouzerh, Séverine Renaudineau, Florence Volatron, Geoffroy Guillemot, Sébastien Blanchard, Guillaume Izzet, Albert Solé-Daura, Josep M. Poblet, and Anna Proust
Subjects: Inorganic Chemistry, Physical and Theoretical Chemistry
Abstract: The mixed molybdenum/tungsten Keggin-type polyoxometalate (POM) hybrid (TBA)
Published: 2022

11. Keggin-type polyoxometalates as Cu(II) chelators in the context of Alzheimer's disease

Author: Elena Atrián-Blasco, Lucie de Cremoux, Xudong Lin, Rufus Mitchell-Heggs, Laurent Sabater, Sébastien Blanchard, Christelle Hureau, 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), Instituto de Nanociencia y Materiales de Aragón (INMA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad de Zaragossa, Institut Parisien de Chimie Moléculaire (IPCM), Chimie Moléculaire de Paris Centre (FR 2769), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and European Project: 638712,H2020,ERC-2014-STG,aLzINK(2015)
Subjects: Anions, animal structures, [SDV.NEU.NB]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology, [CHIM.THER]Chemical Sciences/Medicinal Chemistry, 010402 general chemistry, 01 natural sciences, Catalysis, Alzheimer Disease, mental disorders, Materials Chemistry, Humans, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Chelating Agents, Amyloid beta-Peptides, 010405 organic chemistry, Metals and Alloys, General Chemistry, Polyelectrolytes, 0104 chemical sciences, 3. Good health, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Ceramics and Composites, sense organs, Reactive Oxygen Species, Copper
Abstract: Two Keggin polyoxometalates were used as new copper ligands to counteract the effects of CuII(Amyloid-β) interaction. Their ability to remove CuII from CuII(Amyloid-β), to stop CuII(Amyloid-β) induced formation of reactive oxygen species and to restore apo-like self-assembly of CuII(Amyloid-β) was shown.
Published: 2022
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12. Aqueous synthesis of highly luminescent ternary alloyed Mn-doped ZnSeS quantum dots capped with 2-mercaptopropionic acid

Author: Jordane Jasniewski, Hervé Rinnert, Salima Mabrouk, Raphaël Schneider, Lavinia Balan, Rafik Ben Chaabane, Ghouti Medjahdi, Sébastien Blanchard, Laboratoire Réactions et Génie des Procédés (LRGP), Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL), Laboratoire des Interfaces et Matériaux Avancés [Monastir] (LIMA), Faculté des Sciences de Monastir (FSM), Université de Monastir - University of Monastir (UM)-Université de Monastir - University of Monastir (UM), Institut Jean Lamour (IJL), Université de Lorraine (UL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université d'Orléans (UO), Institut Parisien de Chimie Moléculaire (IPCM), Chimie Moléculaire de Paris Centre (FR 2769), Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Ingénierie des Biomolécules (LIBio), and Université de Lorraine (UL)
Subjects: Materials science, Photoluminescence, Analytical chemistry, Quantum yield, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, core/shell Mn:ZnSeS/ZnS, law.invention, chemistry.chemical_compound, X-ray photoelectron spectroscopy, law, Materials Chemistry, [CHIM]Chemical Sciences, Electron paramagnetic resonance, Thiolactic acid, Dopant, Quantum dots, Mechanical Engineering, Metals and Alloys, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, chemistry, Nanocrystal, Mechanics of Materials, Quantum dot, 2-mercaptopropionic acid, Mn-doped ZnSeS, 0210 nano-technology, Stability
Abstract: International audience; Highly photoluminescent and water dispersible ternary alloyed Mn-doped ZnSeS and core/shell Mn:ZnSeS/ZnS quantum dots (QDs) with pure dopant emission were synthesized through a simple aqueous route using thiolactic acid (2-MPA) as a capping ligand. Transmission electron microscopy and X-ray diffraction show that Mn:ZnSeS nanocrystals are of spherical shape, with a diameter of 2.4 nm and a cubic zinc blende structure. With the overcoating of the ZnS shell, the particle size increases to 3.7 nm, which confirms the epitaxial growth of the shell on Mn:ZnSeS cores. The photoluminescence (PL) quantum yield depends on the Mn loading and reaches 22% for Mn:ZnSeS cores doped with 10% Mn and 41% after the growth of ZnS at the surface of the cores due to the effective elimination of surface-trap states. Mn:ZnSeS QDs exhibit also long PL lifetimes (up to 681 μs) indicating that the emission originates from the spin forbidden Mn 2+ 4 T 1 → 6 A 1 transition. Electron paramagnetic resonance and X-ray photoelectron spectroscopy results suggest that Mn 2+ ions 2 are located at the interface of core/shell Mn:ZnSeS/ZnS QDs. Further, the stability of Mn:ZnSeS/ZnS QDs was also investigated along with their transfer in organic phase using octanethiol.
Published: 2020
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13. Assessing the Electrocatalytic Properties of the {CpRh III } 2+ ‐Polyoxometalate Derivative [H 2 PW 11 O 39 {Rh III Cp(OH 2 )}] 3– towards CO 2 Reduction

Author: Anna Proust, Marcelo Girardi, Dominique Platzer, Sébastien Blanchard, Fethi Bedioui, Sophie Griveau, and Sandra Alves
Subjects: 010405 organic chemistry, Ligand, 010402 general chemistry, 7. Clean energy, 01 natural sciences, Medicinal chemistry, Redox, Non-innocent ligand, 0104 chemical sciences, Catalysis, Inorganic Chemistry, Bipyridine, chemistry.chemical_compound, chemistry, Polyoxometalate, Formate, Acetonitrile
Abstract: Storage of electricity produced intermittently by renewable energy sources is a societal issue. Besides the use of batteries and supercapacitors, conversion of excess electricity into chemical energy is also actively investigated. The conversion of CO2 to fuel or fuel precursors is an option that requires the use of a catalyst to overcome the high activation energy barrier. Of molecular catalysts, metal complexes with polypyridyl ligands are well represented, among which the [Cp*Rh(bpy)Cl] + and [M(bpy)(CO)3X] (M = Re, Mn) complexes. As redox non-innocent ligand, the bipyridine ligand is generally involved in the reduction mechanisms. It is thus tempting to replace it by other redox non-innocent ligands such as vacant polyoxometalates (POMs). We have thus prepared [α-H2PW11O39{Rh(III)Cp*(OH2}] 3-which is closely related to [Cp*Rh(III)(bpy)Cl] + by substitution of the monovacant [PW11O39] 7-Keggin-type POM for the bipyridine ligand. Its activity towards CO2 reduction has been assessed in acetonitrile in the presence of water. Compared to [Cp*Rh(bpy)Cl] + that produces formate selectively over CO and H2, the POM derived catalyst favours proton reduction over CO2 reduction.
Published: 2018
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14. Early burial mud diapirism and its impact on stratigraphic architecture in the Carboniferous of the Shannon Basin, County Clare, Ireland

Author: Charles C. Monson, Christopher R. Fielding, James L. Best, Alexander B. Bryk, Jeff Peakall, Sébastien Blanchard, Edward J. Matheson, Gosia Mahoney, and Kalin J. Howell
Subjects: Paleontology, 010504 meteorology & atmospheric sciences, Stratigraphy, Carboniferous, Geology, Architecture, Diapir, Structural basin, 010502 geochemistry & geophysics, 01 natural sciences, 0105 earth and related environmental sciences
Published: 2018
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15. Dye-Sensitized Photocathodes: Boosting Photoelectrochemical Performances with Polyoxometalate Electron Transfer Mediators

Author: Vincent Artero, Florence Volatron, Youssef Ben M'Barek, Raphaël Salles, Sébastien Blanchard, Murielle Chavarot-Kerlidou, Matthieu Koepf, Jérémy Sum, Jennifer Fize, Timothy E. Rosser, Anna Proust, Guillaume Izzet, Institut Parisien de Chimie Moléculaire (IPCM), Chimie Moléculaire de Paris Centre (FR 2769), Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Solar fuels, hydrogen and catalysis (SolHyCat), Laboratoire de Chimie et Biologie des Métaux (LCBM - UMR 5249), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), ANR-16-CE05-0025,PhotoCarb,Photosynthèse artificielle: du CO2 aux carburants(2016), and ANR-17-EURE-0003,CBH-EUR-GS,CBH-EUR-GS(2017)
Subjects: Materials science, Boosting (machine learning), redox mediator, Energy Engineering and Power Technology, 02 engineering and technology, 010402 general chemistry, Photochemistry, 01 natural sciences, photoelectrochemical cells, law.invention, Electron transfer, law, Materials Chemistry, Electrochemistry, photocathodes, Chemical Engineering (miscellaneous), [CHIM]Chemical Sciences, polyoxometalates, Electrical and Electronic Engineering, nano-ITO, [CHIM.MATE]Chemical Sciences/Material chemistry, Photoelectrochemical cell, 021001 nanoscience & nanotechnology, Cathode, 0104 chemical sciences, Polyoxometalate, 0210 nano-technology, Redox mediator
Abstract: International audience; The amplification effect of polyoxometalates (POMs) on the efficiency of dye-sensitized nano-ITO cathodes is disclosed. The use of hybrid polyoxometalates of the type [PW11O39{SnC6H4 C6H4F}](4-), F standing for a carboxylic group (POM-COOH) or a diazonium unit, allows control of the loading of the POMs on the electrode and investigation of key parameters. Even at very low loading, POM-COON has a substantial effect on the photocurrent response with up to 25-fold increase. Besides ensuring the stability toward leaching, the anchoring function of the POM hybrids was also found to play an intricate role in the competition between the multiple events involved.
Published: 2020
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16. Un duo gagnant pour la catalyse rédox

Author: Maylis Orio, Sébastien Blanchard, Institut des Sciences Moléculaires de Marseille (ISM2), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Edifices PolyMétalliques (E-POM), Institut Parisien de Chimie Moléculaire (IPCM), Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: quantum chemistry, organic radical, selectivity tuning, catalysis, [CHIM]Chemical Sciences, paramagnetic species, non-innocent ligand, electronic structure, EPR spectroscopy
Abstract: International audience; L'utilisation conjointe des mesures expérimentales et des modélisations théoriques constitue un outil pertinent pour étudier les propriétés moléculaires de systèmes catalytiques complexes impliquant des ligands non inno-cents. Cette approche combinée va permettre de déterminer la structure électronique des espèces mises en jeu au cours des réactions redox dans le but de comprendre, de rationaliser et d'optimiser leurs performances catalytiques. Mots-clés Spectroscopie RPE, chimie quantique, ligand non innocent, espèce paramagnétique, radical organique, structure électronique, catalyse, ajustement de la sélectivité. Abstract A winning duo for redox catalysis Coupling experiments and theoretical modeling appears as a valuable tool to study the molecular properties of complex catalytic systems containing non-innocent ligands. This combined approach allows to determine the electronic structure of the species involved during redox reactions with the aim of understanding, rationalizing and optimizing their catalytic performances.
Published: 2019

17. Highly fluorescent, color tunable and magnetic quaternary Ag–In–Mn–Zn–S quantum dots

Author: Halima Alem, Raphaël Schneider, Sébastien Blanchard, Hervé Rinnert, Perizat Galiyeva, Ghouti Medjahdi, Bolat Uralbekov, Lavinia Balan, Laboratoire Réactions et Génie des Procédés (LRGP), Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL), Institut Jean Lamour (IJL), Université de Lorraine (UL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA)), Institut de Science des Matériaux de Mulhouse (IS2M), Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Centre National de la Recherche Scientifique (CNRS), Edifices PolyMétalliques (E-POM), Institut Parisien de Chimie Moléculaire (IPCM), Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Al-Farabi Kazakh National University, Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Al-Farabi Kazakh National University [Almaty] (KazNU), and Balan, Lavinia
Subjects: [CHIM.MATE] Chemical Sciences/Material chemistry, Materials science, Photoluminescence, Analytical chemistry, Quantum yield, 02 engineering and technology, Crystal structure, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Fluorescence, 0104 chemical sciences, Inorganic Chemistry, chemistry.chemical_compound, chemistry, Oleylamine, Quantum dot, Phase (matter), Orthorhombic crystal system, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS
Abstract: Mn-Doped quantum dots (QDs) are of high interest for numerous applications like solar cells, optoelectronics, optosensing, or bioimaging. Here, we report the preparation of quaternary (AgInS2)x(MnS)y(ZnS)1−x−y QDs, thereafter noted Mn : AIZS via a thermally induced decomposition of Ag, In, Zn and Mn precursors in the presence of oleylamine and dodecanethiol. The Mn : AIZS QDs have an average diameter of 3.5 nm and their XRD patterns can be indexed with the orthorhombic phase of AgInS2. The incorporation of Mn2+ ions in the AIZS crystal lattice results in a red-shift of the photoluminescence (PL) emission maximum depending on the Mn2+ content. The PL quantum yields decrease upon loading with Mn2+ but remained high (53–31%) until 50% theoretical loading in Mn2+. Steady state, PL excitation and time-resolved PL measurements suggest that Mn2+-dependent trap states are involved in the PL emission. Mn : AIZS QDs exhibit also magnetic properties. In addition, Mn : AIZS QDs can easily be transferred to the aqueous phase using the PMAO amphiphilic polymer without alteration of their optical properties (PL quantum yield up to 51%), revealing their high potential for biological applications.
Published: 2019
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18. Dolomitization of supratidal to shallow-marine carbonates in the Pennsylvanian successions of the Wyoming Shelf

Author: Christopher R. Fielding, Tracy D. Frank, and Sébastien Blanchard
Subjects: 010506 paleontology, Recrystallization (geology), Permian, Evaporite, Dolomite, Geochemistry, Geology, 010502 geochemistry & geophysics, 01 natural sciences, Diagenesis, Pennsylvanian, Facies, Dolomitization, 0105 earth and related environmental sciences
Abstract: Laterally extensive beds of dolomitized carbonate are found interbedded with eolian to peritidal sandstones in the hydrocarbon-producing Pennsylvanian to earliest Permian successions of the Wyoming Shelf, USA. Subsurface and surface correlations often rely on these dolomite intervals yet their origin is poorly constrained. To characterize the nature of dolomitization, we integrate petrography, carbon and oxygen isotope data, and sedimentological characteristics of pervasively dolomitized shallow-marine, supratidal, and pedogenic facies in the Amsden and Tensleep Formations of the Bighorn Basin (early to middle Pennsylvanian, northern Wyoming). Stable isotopic compositions are compared with the documented isotopic signature of protodolomite forming on present-day arid coastlines. The composition of fine- to medium-grained dolomitized matrix differs from that of late-stage calcite spars, suggesting that dolomites preserve a primary or early diagenetic signal. The δ18O values of dolomites (-1.2 to 7.6‰ VPDB) display a similar range to that of modern protodolomite forming in the tidal flats of the coast of Abu Dhabi. The δ13C values, however, are consistently lower than expected if dolomite had precipitated from sea-water. These relationships suggest that dolomite incorporated a considerable amount of isotopically light carbon during primary formation or later during overgrowth and/or recrystallization of the initial protodolomite. Pennsylvanian and earliest Permian successions in Wyoming, Montana, and northeastern Utah display very similar diagenetic modifications (i.e., pervasive dolomitization, evaporite replacement, silicification), suggesting that the models discussed here may be applicable to these contemporaneous formations.
Published: 2016
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19. C−N Bond Formation from a Masked High-Valent Copper Complex Stabilized by Redox Non-Innocent Ligands

Author: Pauline Chaumont, Marine Desage-El Murr, Jérémy Jacquet, Geoffrey Gontard, Louis Fensterbank, Maylis Orio, Hervé Vezin, Sébastien Blanchard, 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 des Sciences Moléculaires de Marseille (ISM2), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), Méthodes et Application en Chimie Organique (MACO), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Lille, CNRS, Institut des Sciences Moléculaires de Marseille [ISM2], Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 [LASIRE], and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)
Subjects: chemistry.chemical_element, Photochemistry, 010402 general chemistry, Redox, 01 natural sciences, Catalysis, Reductive elimination, Metal, Nucleophile, Oxidation state, redox chemistry, ligand effects, Chemistry, Ligand, 010405 organic chemistry, General Chemistry, reaction mechanisms, copper, density functional calculations, General Medicine, Copper, Non-innocent ligand, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, visual_art, visual_art.visual_art_medium
Abstract: The reactivity of a stable copper(II) complex bearing fully oxidized iminobenzoquinone redox ligands towards nucleophiles is described. In sharp contrast with its genuine low-valent counterpart bearing reduced ligands, this complex performs high-yielding C−N bond formations. Mechanistic studies suggest that this behavior could stem from a mechanism akin to reductive elimination occurring at the metal center but facilitated by the ligand: it is proposed that a masked high oxidation state of the metal can be stabilized as a lower copper(II) oxidation state by the redox ligands without forfeiting its ability to behave as a high-valent copper(III) center. These observations are substantiated by a combination of advanced EPR spectroscopy techniques with DFT studies. This work sheds light on the potential of redox ligands as promoters of unusual reactivities at metal centers and illustrates the concept of masked high-valent metallic species. 55;36
Published: 2016
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20. Sequence stratigraphic framework for mixed aeolian, peritidal and marine environments: Insights from the Pennsylvanian subtropical record of Western Pangaea

Author: Christopher R. Fielding, Tracy D. Frank, James E. Barrick, and Sébastien Blanchard
Subjects: 010506 paleontology, Paleontology, Pangaea, Sequence (geology), Stratigraphy, Pennsylvanian, Aeolian processes, Geology, Subtropics, 010502 geochemistry & geophysics, 01 natural sciences, 0105 earth and related environmental sciences
Published: 2016
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21. Basement influences on dolomite-hosted vertical sedimentary intrusions in marine erg-margin deposits from the Pennsylvanian of Northern Wyoming (USA)

Author: Christopher R. Fielding, Sébastien Blanchard, and Tracy D. Frank
Subjects: geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Lineament, Stratigraphy, Geochemistry, Geology, 010502 geochemistry & geophysics, 01 natural sciences, Diagenesis, Precambrian, Erg (landform), Basement (geology), Pennsylvanian, Intraplate earthquake, Sedimentary rock, Geomorphology, 0105 earth and related environmental sciences
Abstract: Understanding soft-sediment deformation structures and their triggers can help in assessing the influence of tectonics, climate, and diagenesis on the stratigraphic record. Such features commonly record processes that would not otherwise be preserved. The description of soft-sediment deformation in Pennsylvanian deposits of the western United States, characterized by orbitally driven alternations between eolian sandstones, marine dolomites, and shales, has been limited to contorted cross-beds. We document discordant, sheet-like sedimentary intrusions in three marine intervals over a 45-km-wide area. Intrusions consist of very well to moderately cemented, very fine to fine-grained quartz sandstone. Body widths range from 5 to 50 cm, and heights up to 2 m. The orientations of 103 vertical bodies were measured. Based on upward- and downward-tapering, and the presence of deformed, microfractured fragments of host rocks, these intrusions are interpreted to result from seismically induced fluidization of water-saturated sands. Their sheet-like morphology indicates injection through fractures. Two predominant directions (WNW-ESE and N-S) were recognized and interpreted as pre-injection fracture sets. Folding of surrounding layers around the intrusions suggests negligible compaction prior to injection, indicating penecontemporaneous or shallow burial fluidization. The intraplate location of Wyoming implies that seismicity did not originate at a plate boundary. The area within which intrusions are found is crossed by a zone characterized by localized development of thick eolian stories at the top of the formation, interpreted to reflect the rejuvenation of a basement lineament. The seismically active character of lineaments may explain overpressure and fluidization, substantiating the notion that Precambrian structures repeatedly affected Phanerozoic sedimentation. Similar intrusive features may be wrongly identified or overlooked in deposits of arid environments, but their recognition provides insights into structural context during deposition and burial.
Published: 2016
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22. High-Performance Group Transfer Catalysis by Copper Complex with Redox-Active Ligand in an Entatic State

Author: Khaled Cheaib, Yufeng Ren, Hervé Vezin, Desage-El Murr M, Louis Fensterbank, Nicolas Vanthuyne, Jérémy Forté, Maylis Orio, and Sébastien Blanchard
Subjects: Steric effects, Electron transfer, Computational chemistry, Chemistry, Ligand, Entatic state, Reactivity (chemistry), Entasis, Redox, Catalysis
Abstract: Metalloenzymes use earth-abundant non-noble metals to perform high-fidelity transformations in the biological world. To ensure chemical efficiency, metalloenzymes have acquired evolutionary reactivity-enhancing tools. Among these, the entatic state model states that a strong steric distortion induced by ligands around a metal center gives rise to an energized structure called entatic state, strongly improving the reactivity. However, while the original definition refers both to the transfer of electrons or chemical groups, the chemical application of this concept in synthetic systems has mostly focused on electron transfer, therefore eluding chemical transformations. Here we report that a highly-strained redox-active ligand enables a copper complex to perform catalytic nitrogen- and carbon-group transfer in as fast as two minutes, thus exhibiting a strong increase in reactivity compared to its unstrained analogue. This is the first report combining two reactivity-enhancing features from metalloenzymes, entasis and redox cofactors, applied to group-transfer catalysis.
Published: 2019
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23. Detecting unknown chemical clouds at distance with multispectral imagery

Author: Le Brun Gay, Sébastien Blanchard, Sylvain Favier, and Aymeric Alazarine
Published: 2018
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24. Copper-Catalyzed Aziridination with Redox-Active Ligands: Molecular Spin Catalysis

Author: Maylis Orio, Jérémy Jacquet, Marine Desage-El Murr, Sébastien Blanchard, Khaled Cheaib, Yufeng Ren, Louis Fensterbank, Hervé Vezin, Institut des Sciences Moléculaires de Marseille (ISM2), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-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), Chimie organique et macromoléculaire (COM), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), and Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Spin states, 010405 organic chemistry, Chemistry, Ligand, Organic Chemistry, Organometallic catalysis, General Chemistry, 010402 general chemistry, 01 natural sciences, Combinatorial chemistry, Catalysis, 0104 chemical sciences, Copper catalyzed, Redox active, [CHIM]Chemical Sciences, Reactivity (chemistry), ComputingMilieux_MISCELLANEOUS
Abstract: Small-molecule catalysts as mimics of biological systems illustrate the chemists' attempts at emulating the tantalizing abilities displayed by nature's metalloenzymes. Among these innate behaviors, spin multistate reactivity is used by biological systems as it offers thermodynamic leverage towards challenging chemical reactivity but this concept is difficult to translate into the realm of synthetic organometallic catalysis. Here, we report a rare example of molecular spin catalysis involving multistate reactivity in a small-molecule biomimetic copper catalyst applied to aziridination. This behavior is supported by spin state flexibility enabled by the redox-active ligand.
Published: 2018
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25. Impact of continental motion and dynamic glaciations on low-latitude climate during the Carboniferous: The record of the Wyoming Shelf (Western United States)

Author: Christopher R. Fielding, Sébastien Blanchard, and Tracy D. Frank
Subjects: Pangaea, Paleozoic, Paleontology, Climate change, Diachronous, Oceanography, Carboniferous, Pennsylvanian, Ice age, Glacial period, Ecology, Evolution, Behavior and Systematics, Geology, Earth-Surface Processes
Abstract: The dynamic character of the Late Paleozoic Ice Age is evident from glacial deposits, but its impact on tropical climate is not well constrained. Global changes in climate are overprinted on longer-term paleogeographic variations, resulting in a complex time–space distribution of climate-sensitive lithologies. The significance of such lithologies in Carboniferous successions of the western United States has not been fully explored. In this study, we provide new interpretations for the paleoclimatic context of the Amsden and Tensleep Formations (Pennsylvanian, Northern Wyoming, USA). The Amsden Formation consists of a basal sandstone member overlain by red siltstones containing pisolites. Very large-scale (~ 10 m) cross-bedding within the basal sandstone indicates deposition in an erg environment. Iron pisoid-rich layers in the overlying member suggest an evolution toward more humid conditions. Persistent arid conditions during the middle Pennsylvanian are suggested by eolian sandstones and calcretes in the overlying Tensleep Formation. These formations were deposited on the karst topography that developed on top of the lower to middle Mississippian Madison Group. Although the development of karstic features implies that humid conditions prevailed during the late Mississippian, evaporites and evidence for early dolomitization within the formation suggest that it was deposited under arid conditions. These relationships argue for a long-term climate evolution from arid to humid during the Mississippian, and a return to arid conditions during the Pennsylvanian. This trend can be explained by the northward drift from ~ 15°S to ~ 12°N. A comparison with contemporaneous records reveals a diachronous evolution across western Pangaea, with the climatic conditions documented on the Wyoming Shelf being reached later in eastern North America. These relationships indicate that plate motion considerably overprints long-term climatic records. Departures from this trend, suggested by the presence of erg deposits in the basal Amsden Formation, record the overprinting of shorter periods of climate change.
Published: 2015
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26. Electro‐Assisted Reduction of CO 2 to CO and Formaldehyde by (TOA) 6 [α‐SiW 11 O 39 Co(_)] Polyoxometalate

Author: Marcelo Girardi, Philippe Simon, Fethi Bedioui, Sophie Griveau, Marc Fontecave, Anna Proust, Sébastien Blanchard, Institut Parisien de Chimie Moléculaire (IPCM), Chimie Moléculaire de Paris Centre (FR 2769), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Unité de Technologies Chimiques et Biologiques pour la Santé (UTCBS - UM 4 (UMR 8258 / U1022)), Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire de Chimie des Processus Biologiques (LCPB), Collège de France (CdF (institution))-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and GRIVEAU, SOPHIE
Subjects: Electrolysis, Coordination sphere, 010405 organic chemistry, Chemistry, Inorganic chemistry, 010402 general chemistry, Electrocatalyst, Electrochemistry, 01 natural sciences, 0104 chemical sciences, Catalysis, law.invention, Inorganic Chemistry, law, [CHIM] Chemical Sciences, Polyoxometalate, [CHIM]Chemical Sciences, Cyclic voltammetry, Selectivity
Abstract: International audience; We report here on the multiproton-multielectron electrochemical reduction of CO2 in homogeneous solution by using (TOA)6[α-SiW11O39Co(_)] (TOA = tetraoctyl ammonium; _ = vacant position in the coordination sphere of Co) as an electrocatalyst. First, the electrochemical behavior of (TOA)6[α-SiW11O39Co(_)] was analyzed in detail by cyclic voltammetry in dichloromethane, studying the influence of the presence of protons and/or CO2. These preliminary results were further used to optimize the conditions of electrolysis in terms of reduction potentials. Analysis of the electrolysis products in the gas and liquid phases show the formation of CO and HCHO without formation of H2. Our results tend to show that the (TOA)6[α-SiW11O39Co(_)] polyoxometalate is a catalyst for CO2 electroreduction, with unique selectivity.
Published: 2015
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27. A Simple Synthesis of Triangular All-Metal Aromatics Allowing Access to Isolobal All-Metal Heteroaromatics

Author: Yanling Li, Max Malacria, Tatiana Cañeque, Sébastien Blanchard, Yanlan Wang, Raimondo Maggi, Franca Bigi, Pierre-Alexandre Deyris, Florent Blanchard, Giovanni Maestri, Institut des Sciences Moléculaires (ISM), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1 (UB)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie des Substances Naturelles (ICSN), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), 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), Università degli studi di Parma = University of Parma (UNIPR), Géosciences Rennes (GR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), CNRS, UPMC, MIUR, 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), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), University of Parma = Università degli studi di Parma [Parme, Italie], Université de Rennes 1 (UR1), and Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS)
Subjects: metal-metal bonds, heterocycles, Mixed metal, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Chemistry, Organic Chemistry, Inorganic chemistry, Isolobal principle, Aromaticity, aromaticity, General Chemistry, Catalysis, Homonuclear molecule, Metal, Crystallography, Pt clusters, Simple (abstract algebra), metallacycles, visual_art, visual_art.visual_art_medium, Molecule, cluster compounds
Abstract: International audience; A simple synthetic method allows the one-pot assembly of C-3-symmetric, 44-core-valence-electron, triangular Pd or Pt clusters and their heterobimetallic mixed Pd/Pt analogues. These mixed metal complexes are the first examples of stable triangular all-metal heteroaromatics. In contrast to traditional heteroaromatic molecules formed combining main-group elements, they actually retain structural and electronic features of their homonuclear analogues.
Published: 2015
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28. Modeling the Oxygen Vacancy at a Molecular Vanadium(III) Silica-Supported Catalyst

Author: Albert Solé-Daura, Céline Paris, Sébastien Blanchard, Yanling Li, Teng Zhang, Sarah Hostachy, Josep M. Poblet, Jorge J. Carbó, Geoffroy Guillemot, Anna Proust, Institut Parisien de Chimie Moléculaire (IPCM), Chimie Moléculaire de Paris Centre (FR 2769), Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Edifices PolyMétalliques (E-POM), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Chimie Moléculaire de Paris Centre (FR 2769), De la Molécule aux Nanos-objets : Réactivité, Interactions et Spectroscopies (MONARIS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Equipe de Recherche en Matériaux Moléculaires et Spectroscopies (ERMMES)
Subjects: 010405 organic chemistry, Chemistry, POLE 2, Vanadium, chemistry.chemical_element, General Chemistry, 010402 general chemistry, 01 natural sciences, Biochemistry, E-POM, Catalysis, 0104 chemical sciences, chemistry.chemical_compound, Paramagnetism, Colloid and Surface Chemistry, Physical chemistry, [CHIM]Chemical Sciences, ERMMES, Partial oxidation, Singlet state, Ground state, Tetrahydrofuran, Derivative (chemistry)
Abstract: Here we report on the use of a silanol-decorated polyoxotungstate, [SbW9O33(tBuSiOH)3]3\textendash (1), as a molecular support to describe the coordination of a vanadium atom at a single-site on silica surfaces. By reacting [V(Mes)3·thf] (Mes = 2,4,6-trimethylphenyl) with 1 in tetrahydrofuran, the vanadium(III) derivative [SbW9O33(tBuSiO)3V(thf)]3\textendash (2) was obtained. Compound 2 displays the paramagnetic behavior expected for a d2-VIII high spin complex (SQUID measurements) with a triplet electronic ground state (ca. 30 kcal·mol\textendash 1 more stable than the singlet, from DFT calculations). Compound 2 proves to be a reliable model for reduced isolated-vanadium atom dispersed on silica surfaces [(\equivSi\textemdash O)3VIII(OH2)], an intermediate that is often proposed in a Mars\textendash van Krevelen type mechanism for partial oxidation of light alcohols. Oxidation of 2 under air produced the oxo-derivative [SbW9O33(tBuSiO)3VO]3\textendash (3). In compound 2, the d2-electrons are localized in degenerated d(V) orbitals, whereas in the electronically analogous bireduced-[SbW9O33(tBuSiO)3VO]5\textendash, 3·(2e), one electron is localized on d(V) orbital and the second one is delocalized on the polyoxotungstic framework, leading to a unique case of a bireduced heteropolyanion derivative with completely decoupled d1-V(IV) and d1-W(V). Our body of experimental results (EPR, magnetic measurements, spectroelectrochemical studies, Raman spectroscopy) and theoretical studies highlights (i) the role of the apical ligand coordination, i.e., thf (σ-donor) vs oxo (π-donor), in destabilizing or stabilizing the d(V) orbitals relative to the d(W) orbitals, and (ii) a geometrical distortion of the O3VO entity that causes a splitting of the degenerated orbitals and the stabilization of one d(V) orbital in the bireduced compound 3·(2e).
Published: 2018
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29. Detecting unknown chemical clouds at distance with multispectral imagery

Author: Aymeric Alazarine, Sébastien Blanchard, Manon Verneau, Sylvain Favier, and Romain Verollet
Subjects: Infrared, Computer science, Multispectral image, Process (computing), 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Signal, Toxic chemical, 010309 optics, Identification (information), 0103 physical sciences, 0210 nano-technology, Absorption (electromagnetic radiation), Remote sensing
Abstract: In the past, chemical incidents or attacks have often involved mixtures of chemicals or fractional formulations of toxic compounds. Terrorist groups are also likely to generate new toxic chemical agents. These situations involve unknown compounds and thus may be undetectable using traditional methods. Indeed, standoff gas detection with infrared devices traditionally relies on the comparison between measured signal and a library of signals included in a database. Observing the gas absorption in infrared band III (LWIR 8-14 μm), our multispectral infrared camera is used to detect gas clouds up to a range of several kilometers, to provide identification of gas type and to follow the motion of the cloud in real time. The approach described in this paper develops an algorithm that enables the device to detect gas even if the measured signature is not in the database – a pattern-matching-free algorithm. This detection process has been evaluated in the laboratory and subjected to significant experimental feedback. The results are a capability to detect unknown gases and gas mixtures.
Published: 2017
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30. Solid‐State Hierarchical Cyclodextrin‐Based Supramolecular Polymer Constructed by Primary, Secondary, and Tertiary Azido Interactions

Author: Yongmin Zhang, Sébastien Blanchard, Ségolène Adam de Beaumais, Etienne Derat, Laurent Bouteiller, Mickaël Ménand, Matthieu Sollogoub, Lise-Marie Chamoreau, 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), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Méthodes et Application en Chimie Organique (MACO), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Géosciences Rennes (GR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Agence Nationale de la Recherche [ANR-Blanc SIMI 7-2012], LabEx MiChem part of French state funds, ANR within the Investissements d'Avenir programme [ANR-11-IDEX-0004-02], ANR-11-IDEX-0004,SUPER,Sorbonne Universités à Paris pour l'Enseignement et la Recherche(2011), Université de Rennes 1 (UR1), and Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS)
Subjects: chemistry.chemical_classification, cyclodextrins, Primary (chemistry), Cyclodextrin, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Chemistry, inclusion compounds, Supramolecular chemistry, Solid-state, Cooperativity, General Chemistry, Combinatorial chemistry, azides, Catalysis, law.invention, Supramolecular polymers, chemistry.chemical_compound, law, Polymer chemistry, Azide, Crystallization, supramolecular polymers
Abstract: International audience; The crystallization of a di-azido-alpha-cyclodextrin revealed a polymeric self-assembly involving a variety of azido-type interactions. The crystal arrangement relies on the cooperativity of a primary azido inclusion, a secondary azido-azido interaction involving an unprecedented distribution of canonical forms, and a tertiary azido-groove interaction. The second azido group brings in a major contribution to the supramolecular structure illustrating the benefit of a difunctionalization for the generation of hierarchy.
Published: 2014
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31. Solid‐State Hierarchical Cyclodextrin‐Based Supramolecular Polymer Constructed by Primary, Secondary, and Tertiary Azido Interactions

Author: Mickaël Ménand, Ségolène Adam de Beaumais, Lise‐Marie Chamoreau, Etienne Derat, Sébastien Blanchard, Yongmin Zhang, Laurent Bouteiller, and Matthieu Sollogoub
Subjects: General Medicine
Published: 2014
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32. Synthesis of Triangular Tripalladium Cations as Noble-Metal Analogues of the Cyclopropenyl Cation

Author: Emmanuel Lacôte, Geoffrey Gontard, Louis Fensterbank, Max Malacria, Giovanni Maestri, and Sébastien Blanchard
Subjects: Delocalized electron, Crystallography, Atomic orbital, Chemistry, Inorganic chemistry, engineering, chemistry.chemical_element, Aromaticity, Noble metal, General Medicine, engineering.material, Palladium
Abstract: The first C3-symmetric 44-core-valence-electron triangular palladium clusters, [{(SAr′)(PAr3)Pd}3]+, have been synthesized by activation of the CS bond of isothioureas. Owing to delocalized metal–metal bonding, these stable complexes are the first noble-metal analogues of the π-aromatic cyclopropenyl cation [C3H3]+, with their all-metal aromaticity involving d-type atomic orbitals.
Published: 2014
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33. Circumventing Intrinsic Metal Reactivity: Radical Generation with Redox-Active Ligands

Author: Hervé Vezin, Maylis Orio, Khaled Cheaib, Sébastien Blanchard, Marine Desage-El Murr, Louis Fensterbank, Jérémy Jacquet, Yufeng Ren, 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), Chimie organique et macromoléculaire (COM), Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Moléculaires de Marseille (ISM2), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Lille, CNRS, Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 [LASIRE], Institut des Sciences Moléculaires de Marseille [ISM2], and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Institut de Chimie du CNRS (INC)
Subjects: inorganic chemicals, CF3. radicals, nickel, redox-active ligand, single electron transfer, 010405 organic chemistry, Chemistry, Ligand, Radical, Organic Chemistry, chemistry.chemical_element, General Chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, 010402 general chemistry, Photochemistry, 01 natural sciences, Redox, Catalysis, Non-innocent ligand, 0104 chemical sciences, Nickel, Electron transfer, Reactivity (chemistry), [CHIM.COOR]Chemical Sciences/Coordination chemistry
Abstract: International audience; Nickel complexes have gained sustained attention as efficient catalysts in cross‐coupling reactions and co‐catalysts in dual systems due to their ability to react with radical species. Central to this reactivity is nickel's propensity to shuttle through several accessible redox states from Ni0 to NiIV. Here, we report the catalytic generation of trifluoromethyl radicals from a nickel complex bearing redox‐active iminosemiquinone ligands. This unprecedented reactivity is enabled through ligand‐based oxidation performing electron transfer to an electrophilic CF3+ source while the nickel oxidation state is preserved. Additionally, extension of this reactivity to a copper complex bearing a single redox equivalent is reported, thus providing a unified reactivity scheme. These results open new pathways in radical chemistry with redox‐active ligands.
Published: 2017
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34. Enzymatic oxidation of ansa-ferrocifen leads to strong and selective thioredoxin reductase inhibition in vitro

Author: Alberto Bindoli, Alessandra Folda, José de Jesús Cázares-Marinero, Anna Citta, Valeria Scalcon, Michèle Salmain, Sébastien Blanchard, Pascal Pigeon, Yong Wang, Anne Vessières, Ilaria Ciofini, Maria Pia Rigobello, Gérard Jaouen, Dipartimento di Scienze Biomediche Sperimentali, Universita degli Studi di Padova, Istituto di Neuroscienze - Sezione di Padova, Institut Parisien de Chimie Moléculaire (IPCM), Chimie Moléculaire de Paris Centre (FR 2769), Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche de Chimie Paris (IRCP), Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC), Université Paris sciences et lettres (PSL), Chemical Biology (CHEMBIO), and Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Chimie Moléculaire de Paris Centre (FR 2769)
Subjects: Saccharomyces cerevisiae Proteins, Thioredoxin-Disulfide Reductase, Stereochemistry, Thioredoxin reductase, Glutathione reductase, Quinone methide radical, Saccharomyces cerevisiae, [CHIM.THER]Chemical Sciences/Medicinal Chemistry, 010402 general chemistry, 01 natural sciences, Biochemistry, Redox, Horseradish peroxidase, Ansa-ferrocifen, Inorganic Chemistry, chemistry.chemical_compound, Enzymatic oxidation, Ferrous Compounds, Horseradish Peroxidase, biology, 010405 organic chemistry, Chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Quinone methide, Enzyme assay, 0104 chemical sciences, 3. Good health, Iodoacetamide, biology.protein, Ferrocene, Oxidation-Reduction, [CHIM.CHEM]Chemical Sciences/Cheminformatics, Cysteine
Abstract: International audience; This paper reports the inhibitory effect on the cytosolic thioredoxin reductase (TrxR1) in vitro by the ansa-ferrocifen derivative (ansa-FcdiOH, 1). We found that 1 decreased only slightly enzyme activity (IC50 = 8 μM), while 1*, the species generated by enzymatic oxidation by the HRP (horseradish peroxidase)/H2O2 mixture, strongly inhibited TrxR1 (IC50 = 0.15 μM). At the same concentrations, neither 1 nor 1* had effect on glutathione reductase (GR). The most potent TrxR1 inhibitor did not appear to be the corresponding quinone methide as it was the case for ferrocifens of the acyclic series, or the stabilized carbocation as in the osmocifen series, but rather the quinone methide radical. This hypothesis was confirmed by ab-initio calculations of the species generated by oxidation of 1 and by EPR spectroscopy. BIAM (biotin-conjugated iodoacetamide) assay showed that 1* targeted both cysteine and selenocysteine of the C-terminal redox center of TrxR1.
Published: 2016
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35. Non‐Innocent Ligands: New Opportunities in Iron Catalysis

Author: Virginie Mouriès-Mansuy, Etienne Derat, Louis Fensterbank, Marine Desage-El Murr, Max Malacria, Sébastien Blanchard, Géosciences Rennes (GR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-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), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Agence Nationale pour la Recherche (ANR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), and Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Redox chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Chemistry, Iron, 010402 general chemistry, 01 natural sciences, Combinatorial chemistry, Redox, Non-innocent ligand, 0104 chemical sciences, Catalysis, Inorganic Chemistry, Density functional calculations, Non-innocent ligands (NILs), Organic chemistry, Low-valent iron complexes
Abstract: International audience; Introduced in the late sixties, non-innocent (or redox) ligands have been extensively studied for their unusual and intriguing chemical behavior. Their ability to delocalize and/or provide electrons to the metal center of organometallic complexes confers them undisputable chemical interest and has proved valuable in the development of novel synthetic methodologies. This review will focus on the chemistry and applications of low-valent iron complexes bearing potentially non-innocent ligands. Because of the elusive nature of these ligands, and whenever possible, theoretical calculations and analysis of spectroscopic data will be presented in an effort to provide insights into the catalytic activity of the complexes.
Published: 2011
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36. Electroactive Benzothiazole Hydrazones and Their [Mo6O19]2− Derivatives: Promising Building Blocks for Conducting Molecular Materials

Author: Pierre Gouzerh, Anna Proust, Kamal Boubekeur, Bernd Schöllhorn, Sébastien Blanchard, and Sylvain Gatard
Subjects: chemistry.chemical_classification, Pi system, Organic Chemistry, chemistry.chemical_element, Hydrazone, General Chemistry, Catalysis, chemistry.chemical_compound, chemistry, Benzothiazole, Molybdenum, Polymer chemistry, X-ray crystallography, Organic chemistry, Molecule, Cyclic voltammetry, Acetonitrile
Abstract: The electroactive benzothiazole hydrazone AMBTH-H(2), a new member of the 2,2'-azino-bis(N-alkylbenzothiazole) family, was synthesised in a five-step procedure and characterised by using X-ray diffraction along with two intermediates and the N-methylbenzothiazole hydrazone MBTH-H(2). Both AMBTH-H(2) and MBTH-H(2) were coupled to [Mo(6)O(19)](2-) in acetonitrile in the presence of dicyclohexylcarbodiimide and dimethylaminopyridine to give two new diazoalkane-hexamolybdates, which were isolated as tetrabutylammonium salts and characterised by using IR, UV/Vis and NMR spectroscopies, cyclic voltammetry and, for one of them, X-ray diffraction. The packing arrangement molecules in crystals of AMBTH-H(2), the redox features of the AMBTH-hexamolybdate hybrid together with a good electronic communication between the organic pi system and the molybdenum centres make these compounds very promising blocks for the synthesis of conducting molecular materials.
Published: 2010
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37. Redox-ligand sustains controlled generation of CF 3 radicals by well-defined copper complex

Author: Etienne Derat, Jérémy Jacquet, Louis Fensterbank, Marine Desage-El Murr, Sébastien Blanchard, Institut Parisien de Chimie Moléculaire (IPCM), Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Edifices PolyMétalliques (E-POM), Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010405 organic chemistry, Ligand, Trifluoromethylation, Radical, chemistry.chemical_element, General Chemistry, 010402 general chemistry, Photochemistry, 01 natural sciences, Copper, Redox, Enol, 0104 chemical sciences, Catalysis, chemistry.chemical_compound, chemistry, Electrophile, Organic chemistry, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract: International audience; A well-defined copper complex bearing iminosemiquinone ligands performs single electron reduction of an electrophilic CF3+ source into CF˙3 radicals. This redox behavior is enabled by the ligand which shuttles through two different redox states (iminosemiquinone and iminobenzoquinone) while the copper center is preserved as a Cu(II). This system was used in the trifluoromethylation of silyl enol ethers, heteroaromatics and in the hydrotrifluoromethylation of alkynes. This is the first example of cooperative redox catalysis for the controlled generation of CF˙3 radicals.
Published: 2016
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38. Synthesis and Characterization of the Keggin-Type Ruthenium-Nitrido Derivative [PW11O39{RuN}]4- and Evidence of Its Electrophilic Reactivity

Author: Kamal Boubekeur, Sébastien Blanchard, F. Villain, Lise-Marie Chamoreau, Anna Proust, Vanina Lahootun, Claire Besson, René Thouvenot, and Richard Villanneau
Subjects: Extended X-ray absorption fine structure, chemistry.chemical_element, Iminium, General Medicine, General Chemistry, Nuclear magnetic resonance spectroscopy, Photochemistry, Biochemistry, Catalysis, Ruthenium, chemistry.chemical_compound, Crystallography, Colloid and Surface Chemistry, chemistry, Oxidation state, Reactivity (chemistry), Triphenylphosphine, Derivative (chemistry)
Abstract: The ruthenium-nitrido POM derivative [PW11O39{RuVIN}]4- has been synthesized by reaction between [PW11O39]7- and [RuVINCl5]2- or [RuVINCl4]-. Its molecular structure has been confirmed from multinuclear 31P and 183W NMR spectroscopy together with an EXAFS study, while the oxidation state of the ruthenium bearing the nitrido ligand has been inferred both from 183W NMR and XANES analysis at the Ru-K edge. The potential of [PW11O39{RuVIN}]4- in N-atom transfer reactions has been demonstrated through reaction with triphenylphosphine, which ultimately leads to the release of the bis(triphenylphosphane)iminium cation [PPh3=N=PPh3]+ through several intermediates, among which the phosphoraniminato derivative [PW11O39{RuVNPh3}]3- has been structurally characterized. Its unusual oxidation state is in accordance with its EPR spectrum.
Published: 2007
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39. Redox-ligand sustains controlled generation of CF

Author: Jérémy, Jacquet, Sébastien, Blanchard, Etienne, Derat, Marine, Desage-El Murr, and Louis, Fensterbank
Subjects: Chemistry, genetic structures
Abstract: Cooperative catalysis involving copper(ii) complex bearing redox ligands allows generation of CF˙3 radicals through ligand-based SET while metallic oxidation state is preserved., A well-defined copper complex bearing iminosemiquinone ligands performs single electron reduction of an electrophilic CF3+ source into CF˙3 radicals. This redox behavior is enabled by the ligand which shuttles through two different redox states (iminosemiquinone and iminobenzoquinone) while the copper center is preserved as a Cu(ii). This system was used in the trifluoromethylation of silyl enol ethers, heteroaromatics and in the hydrotrifluoromethylation of alkynes. This is the first example of cooperative redox catalysis for the controlled generation of CF˙3 radicals.
Published: 2015

40. Modulating the affinity and the selectivity of engineered calmodulin EF-Hand peptides for lanthanides

Author: Véronique Montjardet-Bas, Sébastien Blanchard, Mélanie Figuet, Loïc Le Clainche, and Claudio Vita
Subjects: Calmodulin, Stereochemistry, Molecular Sequence Data, Bioengineering, Peptide, Biosensing Techniques, Plasma protein binding, Protein Engineering, Lanthanoid Series Elements, Applied Microbiology and Biotechnology, Structure-Activity Relationship, Isomerism, Amino Acid Sequence, Binding site, Peptide sequence, chemistry.chemical_classification, Binding Sites, biology, EF hand, Amino acid, Dissociation constant, Spectrometry, Fluorescence, Amino Acid Substitution, chemistry, biology.protein, Peptides, Protein Binding, Biotechnology
Abstract: A set of engineered peptides (33 amino acids long) corresponding to the helix-turn-helix (EF-Hand) motif of the metal-binding site I of the protein calmodulin from paramecium tetraurelia have been synthesized. A disulfide bridge has been introduced in the native sequence in order to stabilize a native-like conformation. The calcium-binding carboxylate residues in positions 20, 22, 24, and 31 were mutated into other amino acids and the influence of such mutations on the binding affinity of the peptides for calcium and lanthanides have been studied. It was shown that the binding affinity for terbium ions can be modulated with dissociation constants ranging from 40 nmolar to 40 mmolar. The study of the influence of the mutations on the terbium affinity showed that the residue in position 24 played a key role on the capability of the peptides to bind lanthanides and that the affinity could be enhanced by mutations on non-coordinating positions. Such peptides with high affinity for lanthanides may facilitate the development of new highly sensitive biosensors to monitor the metal pollution in the environment.
Published: 2006
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41. X- and Q-Band EPR Studies of the Dinuclear Mn(II) Complex [(Bpmp)Mn2(μ-OAc)2]+. Determination of the Spin Parameters for the S = 1 and S = 2 Spin States

Author: Martine Nierlich, Geneviève Blondin, Eric Rivière, Jean-Jacques Girerd, and Sébastien Blanchard
Subjects: Spin states, Chemistry, Exchange interaction, Analytical chemistry, Magnetic susceptibility, Ion, law.invention, Inorganic Chemistry, Crystallography, Octahedron, law, Antiferromagnetism, Physical and Theoretical Chemistry, Spin (physics), Electron paramagnetic resonance
Abstract: A new mu-phenoxo-bis-mu-acetato di-Mn(II) complex using the BpmpH ligand was isolated as a perchlorate salt (BpmpH = 2,6-bis[bis(2-pyridylmethyl)aminomethyl]-4-methyl-phenol). The X-ray structure has been solved showing that the two Mn(II) ions are in a distorted octahedral environment. Investigation of the variation of the molar magnetic susceptibility upon temperature reveals an antiferromagnetic exchange interaction between the two high-spin Mn(II) ions. Fitting of the experimental data led to g = 1.99 and J = 9.6 cm(-1) (H(HDvV) = JS(A).S(B)). EPR spectra recorded on a powder sample of [(Bpmp)Mn(2)(mu-OAc)(2)](ClO(4)).0.5H(2)O at X-band between 4.3 K and room temperature and at Q-band between 5 and 298 K are presented. A new method based on a scrupulous examination of the variation upon temperature of these experimental spectra is developed here to first assign the transitions to the relevant spin states and second to determine the associated spin parameters. This approach is compared to the deconvolution process that has been previously applied to dinuclear Mn(II) complexes or metalloenzyme active sites. Crystallographic data is as follows: triclinic, space group P one macro, a = 10.154(2) A, b = 12.0454(2) A, c = 17.743(4) A, alpha = 101.69(3) degrees, beta = 93.62(3) degrees, gamma = 94.67(3) degrees, Z = 2.
Published: 2003
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42. ChemInform Abstract: Tandem C-H Activation/Arylation Catalyzed by Low-Valent Iron Complexes with Bisiminopyridine Ligands

Author: Sébastien Blanchard, Louis Fensterbank, Marine Desage-El Murr, Elise Salanouve, Etienne Derat, and Ghania Bouzemame
Subjects: Electron transfer, Tandem, Chemistry, Ligand, Substrate (chemistry), sense organs, General Medicine, Medicinal chemistry, Catalysis
Abstract: The reaction is proposed to proceed through a metal-based inner-sphere C-H activation involving concomitant electron transfer from the ligand and the substrate.
Published: 2014
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43. Iminosemiquinone radical ligands enable access to a well-defined redox-active Cu(II)-CF₃ complex

Author: Jérémy, Jacquet, Elise, Salanouve, Maylis, Orio, Hervé, Vezin, Sébastien, Blanchard, Etienne, Derat, Marine, Desage-El Murr, and Louis, Fensterbank
Subjects: Magnetic Resonance Spectroscopy, Coordination Complexes, Benzoquinones, Electron Spin Resonance Spectroscopy, Electrochemical Techniques, Ligands, Oxidation-Reduction, Copper
Abstract: The reaction of a copper complex bearing iminosemiquinone ligands with a CF3(+) source provides an unprecedented Cu(II)-CF3 complex through ligand-based oxidation. Reactivity of this complex leads to nucleophilic trifluoromethylation of the ligand, suggesting an electronic interplay that results in a formal umpolung of the initial CF3(+).
Published: 2014

44. Oxo-Centered Trinuclear Chromium(III) Complexes with Both Carboxylate and Amidoximate Ligands

Author: Anna Proust, Kamal Boubekeur, Sébastien Blanchard, Patrick Herson, Pierre Gouzerh, Yanling Li, Adrian-Raul Tomsa, Institut Parisien de Chimie Moléculaire (IPCM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Babes-Bolyai University [Cluj-Napoca] (UBB), Edifices PolyMétalliques (E-POM), Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Ethanol, Ligand, Stereochemistry, chemistry.chemical_element, General Chemistry, Condensed Matter Physics, Biochemistry, Medicinal chemistry, 3. Good health, Catalysis, law.invention, Chromium, chemistry.chemical_compound, Magnetization, chemistry, law, Sodium benzoate, [CHIM]Chemical Sciences, General Materials Science, Carboxylate, Electron paramagnetic resonance, ComputingMilieux_MISCELLANEOUS
Abstract: Compounds [Cr 3 III (μ3-O)(O2CPh)5(H2N-sao)(EtOH)2]·EtOH (1·EtOH) and [Cr 3 III (μ3-O)(O2CPh)3(H2N-pao)3]NO3·H2N-paoH·EtOH (2·NO3·H2N-paoH·EtOH) have been obtained either in a sequential one-pot, two-step procedure in which Cr(NO3)3·9H2O is first reacted with sodium benzoate in ethanol under reflux, followed by the addition of salicylamidoxime (H2N-saoH2) or pyridine-2-amidoxime (H2N-paoH), or in a one-step protocol starting from [Cr 3 III (μ3-O)(O2CPh)6(EtOH)3]NO3. They were characterized by single-crystal X-ray diffraction, magnetometry and EPR spectroscopy. Complexes 1 and 2 are derived from the parent complex [Cr 3 III (μ3-O)(O2CPh)6(EtOH)3]+ by replacement of one and three benzoate ligands, respectively, by oximate ligands. The salicylamidoximate and pyridine-2-amidoximate ligands display a tridentate coordination mode with the N–O oximate group bridging a pair of Cr atoms and the additional ligating atom substituting for an ethanol ligand of the parent complex. In both cases susceptibility, magnetization and EPR data reveal a S T = 1/2 ground state with a nearly isotropic g-tensor.
Published: 2014
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45. Tandem C-H Activation/Arylation Catalyzed by Low-Valent Iron Complexes with Bisiminopyridine Ligands

Author: Etienne Derat, Elise Salanouve, Marine Desage-El Murr, Ghania Bouzemame, Sébastien Blanchard, Louis Fensterbank, 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), Géosciences Rennes (GR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Agence Nationale de la Recherche, ANR JCJC, ('UNILVERSAL' project) [ANR-11-JS07-004-01], Universite Pierre & Marie Curie (UPMC, Paris 6), Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), and ANR-11-JS07-0004,UNILVERSAL,Utilisation de complexes de ligands Non-Innocents comme alternatives aux métaux nobles(2011)
Subjects: catalysis, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Aryl, Radical, Organic Chemistry, Substrate (chemistry), Halide, Infrared spectroscopy, CH activation, General Chemistry, redox-active ligands, Photochemistry, Medicinal chemistry, Catalysis, chemistry.chemical_compound, iron, chemistry, Transition metal, IR spectroscopy, Reactivity (chemistry)
Abstract: International audience; Tandem CH activation/arylation between unactivated arenes and aryl halides catalyzed by iron complexes that bear redox-active non-innocent bisiminopyridine ligands is reported. Similar reactions catalyzed by first-row transition metals have been shown to involve substrate-based aryl radicals, whereas our catalytic system likely involves ligand-centered radicals. Preliminary mechanistic investigations based on spectroscopic and reactivity studies, in conjunction with DFT calculations, led us to propose that the reaction could proceed through an inner-sphere CH activation pathway, which is rarely observed in the case of iron complexes. This bielectronic noble-metal-like behavior could be sustained by the redox-active non-innocent bisiminopyridine ligands.
Published: 2014
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46. Calix[6]arene-based models for mono-copper enzymes: a promising supramolecular system for oxidation catalysis

Author: Loïc Le Clainche, Michel Giorgi, Olivier Sénèque, Morgan Campion, Yves Le Mest, Arthur F. Duprat, Sébastien Blanchard, Yannick Rondelez, and Olivia Reinaud
Subjects: Supramolecular chemistry, chemistry.chemical_element, General Chemistry, Electrochemistry, Copper, Catalysis, chemistry.chemical_compound, chemistry, Calixarene, Pyridine, Polymer chemistry, Organic chemistry, Imidazole, Reactivity (chemistry)
Abstract: A novel supramolecular system that mimics the mono-copper site of enzymes is described. It is based on a calix[6]arene presenting either three pyridine (Py) or three imidazole (Im) groups that coordinate the copper center. Whereas Cu(I) is tetrahedral, Cu(II) is 5-coordinate. In both cases however, the Cu complexes possess a labile site located inside the calixarene cavity. A comparative study of the Py- and Im-based systems is presented in terms of chemical behaviour, electrochemistry and reactivity in the presence of hydrogen peroxide. Hence, the Py-based Cu(II) complex appears as the most interesting catalyst for the oxidation of aromatics and alcohols
Published: 2000
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47. Calixarene-Based Copper(I) Complexes as Models for Monocopper Sites in Enzymes

Author: Marie-Noëlle Rager, Loïc Le Clainche, Arthur F. Duprat, Olivia Reinaud, Sébastien Blanchard, Yves Le Mest, Benoît Chansou, and Jean-Pierre Tuchagues
Subjects: chemistry.chemical_classification, Ligand, Inorganic chemistry, chemistry.chemical_element, Bioinorganic chemistry, General Chemistry, Copper, Catalysis, Coordination complex, chemistry.chemical_compound, Enzyme, chemistry, Polymer chemistry, Calixarene, Acetonitrile
Abstract: A cavity that acts as a molecular funnel is formed from calix[6]arene 1 and [CuI (NCCH3 )4 ]PF6 [Eq. (a)]. An exchange of the well-protected acetonitrile ligand for other nitriles RCN is only possible with small R groups. The protection of the copper ions precludes oxidative dimerization; thus, the complexes mimic the mononuclear site of copper enzymes.
Published: 1998
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48. Iminosemiquinone radical ligands enable access to a well-defined redox-active CuII-CF3 complex

Author: Maylis Orio, Elise Salanouve, Louis Fensterbank, Marine Desage-El Murr, Hervé Vezin, Etienne Derat, Sébastien Blanchard, Jérémy Jacquet, 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), Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), Edifices PolyMétalliques (E-POM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nucleophile, Semiquinone, Stereochemistry, Imine, Ligand, 010402 general chemistry, 01 natural sciences, Redox, Methylation, Catalysis, Umpolung, chemistry.chemical_compound, Reaction analysis, Materials Chemistry, Radical, Reactivity (chemistry), 010405 organic chemistry, Trifluoromethylation, Copper complex, Metals and Alloys, article, Complex formation, General Chemistry, Combinatorial chemistry, 0104 chemical sciences, 3. Good health, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, ComputingMethodologies_PATTERNRECOGNITION, chemistry, Ceramics and Composites, Oxidation reduction reaction
Abstract: The reaction of a copper complex bearing iminosemiquinone ligands with a CF3+ source provides an unprecedented CuII-CF3 complex through ligand-based oxidation. Reactivity of this complex leads to nucleophilic trifluoromethylation of the ligand, suggesting an electronic interplay that results in a formal umpolung of the initial CF3+.
Published: 2014
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49. Dépôts volcano-sédimentaires Triasiques du Bassin de Luang Prabang (Laos) : étude sédimentologique et géochronologique

Author: Camille Rossignol, Sébastien Blanchard, Sylvie BOURQUIN, Marie-Pierre Dabard, Erwan Hallot, Marc Poujol, Thierry Nalpas, Géosciences Rennes (GR), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Terre, Temps, Traçage, Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 1 (UR1), Association des Sédimentologistes Français, Dubigeon, Isabelle, Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), and Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)
Subjects: [SDU.STU] Sciences of the Universe [physics]/Earth Sciences, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences
Abstract: National audience; Si la présence de dépôts volcano-sédimentaires est reconnue de longue date dans de nombreux bassins triasiques du domaine Est-Téthysien (correspondant à l'actuelle Asie du Sud Est), leur nature et leur âge n'ont fait l'objet que d'un nombre restreint d'études, portant essentiellement sur la composante volcanique. Or ces dépôts constituent une part importante du remplissage des bassins sédimentaires Est-Téthysien et sont susceptibles d'apporter des informations clefs sur l'évolution géodynamique de cette région au Trias, actuellement largement débattue (e.g. Metcalfe, 2013 et références associées). Des dépôts volcano-sédimentaires continentaux ont récemment été mis en évidence dans le bassin de Luang Prabang (Nord Laos) qui se localise au Trias au carrefour de différents blocs continentaux (Bercovici et al., 2012). Ces dépôts ont fait l'objet d'une étude combinée - sédimentologie de faciès, pétrographie et géochronologie U-Pb sur zircon (Blanchard et al., 2013) - dont les premiers résultats sont les suivants : (i) les séries volcano-sédimentaires se sont mises en place dans des environnements fluviatiles proximaux (cônes alluviaux ou systèmes en tresses) ; (ii) les caractéristiques pétrographiques et la succession des âges maximum (obtenus par la méthode U-Pb sur zircons) suivant la succession stratigraphique dénote du caractère synsédimentaire du volcanisme ; (iii) l'existence d'un volcanisme synsédimentaire atteste la présence d'un volcanisme actif dans cette région au Trias supérieur (225 à 216 Ma) ; (iv) d'autres sources ont également participé au remplissage du bassin, dont une composante d'âge Protérozoïque (1870 Ma) ; (v) les taux de préservation dans cet environnement montrent des variations importantes comprises entre 3 et 100 m.Ma-1. La notion de volcanisme synsédimentaire (dépôts volcaniques interstratifiés versus remaniés au sein des séries sédimentaires) et les échelles de temps associées au caractère synsédimentaire de dépôts volcanosédimentaires est enfin discutée à l'aulne de ces résultats.
Published: 2013

50. Late Triassic volcanic activity in South-East Asia: New stratigraphical, geochronological and paleontological evidence from the Luang Prabang Basin (Laos)

Author: Bernard Battail, Thierry Nalpas, Marie-Pierre Dabard, Nour-Eddine Jalil, Jean-Louis Paquette, Sotsy Vongphamany, José B. Diez, Jean-Sébastien Steyer, Sylvie Bourquin, Monette Veran, Marc Poujol, Sébastien Blanchard, Bounxou Khenthavong, Erwan Hallot, Renaud Vacant, Camille Rossignol, Antoine Bercovici, Géosciences Rennes (GR), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Centre de recherche sur la Paléobiodiversité et les Paléoenvironnements (CR2P), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Département de Géologie [FSSM], Faculté des Sciences Semlalia Marrakech, Department of Geology, Lund University, Sölvegatan 12, SE-22362 Lund, Sweden, Universidade de Vigo, Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Autorité Nationale pour la Science et la Technologie, Musée des Dinosaures, PO Box 739, Savannakhet, Lao Democratic People’s Republic, Département du Patrimoine, des Musées et de l’Archéologie, Settathirath Road, PO Box 122, Vientiane, Lao Democratic People’s Republic, Terre, Temps, Traçage, Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Faculté des Sciences Semlalia [Marrakech], Université Cadi Ayyad [Marrakech] (UCA)-Université Cadi Ayyad [Marrakech] (UCA), Lund University [Lund], Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), and Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: U-Pb geochronology, 010504 meteorology & atmospheric sciences, Permian, Luang Prabang Basin, Dicynodont, [SDE.MCG]Environmental Sciences/Global Changes, Kannemeyeriiformes, [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, Volcaniclastic continental deposits, Structural basin, 010502 geochemistry & geophysics, 01 natural sciences, Paleontology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, U–Pb geochronology, 0105 earth and related environmental sciences, Earth-Surface Processes, [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, geography, geography.geographical_feature_category, biology, Geology, Sedimentary basin, biology.organism_classification, Triassic, Basement (geology), [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Geochronology, Syncline, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology
Abstract: International audience; In South-East Asia, sedimentary basins displaying continental Permian and Triassic deposits have been poorly studied. Among these, the Luang Prabang Basin (North Laos) represents a potential key target to constrain the stratigraphic and structural evolutions of South-East Asia. A combined approach involving sedimentology, palaeontology, geochronology and structural analysis, was thus implemented to study the basin. It resulted in a new geological map, in defining new formations, and in proposing a complete revision of the Late Permian to Triassic stratigraphic succession as well as of the structural organization of the basin. Radiometric ages are used to discuss the synchronism of volcanic activity and sedimentation. The Luang Prabang Basin consists of an asymmetric NE-SW syncline with NE-SW thrusts, located at the contact between Late Permian and Late Triassic deposits. The potential stratigraphic gap at the Permian- Triassic boundary is therefore masked by deformation in the basin. The Late Triassic volcaniclastic continental deposits are representative of alluvial plain and fluvial environments. The basin was fed by several sources, varying from volcanic, carbonated to silicic (non-volcanic). U-Pb dating of euhedral zircon grains provided maximum sedimentation ages. The stratigraphic vertical succession of these ages, from ca. 225, ca. 220 to ca. 216 Ma, indicates that a long lasting volcanism was active during sedimentation and illustrates significant variations in sediment preservation rates in continental environments (from 100 m/Ma to 3 m/Ma). Anhedral inherited zircon grains gave older ages. A large number of them, at ca. 1870 Ma, imply the reworking of a Proterozoic basement and/or of sediments containing fragments of such a basement. In addition, the Late Triassic (Carnian to Norian) sediments yielded to a new dicynodont skull, attributed to the Kannemeyeriiform group family, from layers dated in between 225 and 221 Ma (Carnian).
Published: 2013
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