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1. 1,1-Bis(4-hydroxyphenyl)-2-ferrocenylbutane.

Author

Forté, Jérémy, Herson, Patrick, and Pigeon, Pascal

Subjects
*BIOACTIVE compounds, *DOUBLE bonds, *ORGANOMETALLIC compounds, *X-ray diffraction, *ELEMENTAL analysis
Abstract

Ferrociphenols are anticancer organometallic molecules bearing a ferrocene group linked, at least, to one para-phenol moiety via a double bond. Up to the present, their biological activity has been thought to be linked to their oxidation within cells to form a reactive quinone-methide metabolite with the participation of this central double bond. To prove this assertion, the alkenyl entity of ferrociphenol 1a (1,1-bis-(4-hydroxyphenyl)-2-ferrocenylbut-1-ene) was reduced by triethylsilane in an acidic medium to obtain the alkyl counterpart 1,1-bis(4-hydrophenyl)-2-ferrocenylbutane. 1,1-bis(4-hydrophenyl)-2-ferrocenylbutane was fully characterized by 1H NMR (including COSY), 13C NMR, HRMS, IR, elemental analysis and X-ray diffraction (XRD). Although missing the central double bond, this compound remains biologically active, opening the way to a new family of anticancer ferrocene-containing molecules. [ABSTRACT FROM AUTHOR]

Published
2024
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6. Rational design of a new class of heterobimetallic molecule-based magnets: Synthesis, crystal structures, and magnetic properties of oxamato-bridged [formula omitted] (M′ = Li I and Mn II; M = Ni II and Co II) open-frameworks with a three-dimensional honeycomb architecture

Author

Cangussu, Danielle, Pardo, Emilio, Dul, Marie-Claire, Lescouëzec, Rodrigue, Herson, Patrick, Journaux, Yves, Pedroso, Emerson F., Pereira, Cynthia L.M., Stumpf, Humberto O., Carmen Muñoz, M., Ruiz-García, Rafael, Cano, Joan, Julve, Miguel, and Lloret, Francesc

Published
2008
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8. Trapping of hemiquinone radicals at Mo and P sites by phosphide-bridged dimolybdenum species: Chemistry of complexes [Mo([eta.sup.5]-C5H5)2(OC6H4OH)([mu]-PR2)(CO)4] and [[Mo([eta.sup.5]-C5H5)2{[mu]-PR(OC6H4OH)}(CO)4].sup.-] (R= Cy, Ph)

Author

Alvarez, Celedonio M., Alonso, Maria, Garcia, M. Esther, Herson, Patrick, Rueda, M. Teresa, and Ruiz, Miguel A.

Subjects
Molybdenum compounds -- Chemical properties, Quinone -- Chemical properties, Phosphorus compounds -- Chemical properties, Chemistry
Abstract

The preparation and reactions of the salts [H-DBU][Mo2Cp2([mu]-PR2)(CO)4] and [H-DBU][Mo2Cp2([mu]-PHR)(CO)4] with p-benzoquinone (R= Cy, Ph) is reported. The oxidation reactions reported result in either O-coordination of the hemiquinone radical to the metal center or, if a P-H bond is present in the phosphide bridge, its incorporation at the phosphorus site.

Published
2006

9. Zirconium-substituted isopolytungstates: Structural models for zirconia-supported tungsten catalysts

Author

Carabineiro, Hugo, Villanneau, Richard, Carrier, Xavier, Herson, Patrick, Lemos, Francisco, Ribeiro, Fernando Ramoa, Proust, Anna, and Che, Michel

Subjects
Tungsten compounds -- Chemical properties, Tungsten compounds -- Structure, Catalysts -- Chemical properties, Catalysts -- Structure, Chemistry
Abstract

The synthesis and characterization of a series of mixed W-Zr polynuclear Lindqvist-type complexes, deriving from hexatungstate [W6O19](super 2-), are reported. This spectroscopic characterization has provided useful standards for the study of heterogeneous tungstated zirconia catalysts, which is important for the skeletal isomerization of light n-alkanes.

Published
2006

13. Probing the Local Magnetic Structure of the [FeIII(Tp)(CN)3]- Building Block Via Solid-State NMR Spectroscopy, Polarized Neutron Diffraction, and First-Principle Calculations

Author

De, Siddhartha, Flambard, Alexandrine, Garnier, Delphine, Herson, Patrick, Köhler, Frank H, Mondal, Abhishake, Costuas, Karine, Gillon, Béatrice, Lescouëzec, Rodrigue, Le Guennic, Boris, Gendron, Frédéric, 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), Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM), Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), LLB - Nouvelles frontières dans les matériaux quantiques (NFMQ), Laboratoire Léon Brillouin (LLB - UMR 12), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, 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), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and European Project: 725184,H2020-EU.1.1. - EXCELLENT SCIENCE - European Research Council (ERC),MULTIPROSMM(2017)

Subjects
NMR spectroscopy, ab-initio calculations, neutron diffraction, spin density, density functional calculations, Condensed Matter::Strongly Correlated Electrons, [CHIM.COOR]Chemical Sciences/Coordination chemistry, magnetic properties
Abstract

International audience; The local magnetic structure in the [Fe (Tp)(CN) ] building block was investigated by combining paramagnetic Nuclear Magnetic Resonance (pNMR) spectroscopy and polarized neutron diffraction (PND) with first-principle calculations. The use of the pNMR and PND experimental techniques revealed the extension of spin-density from the metal to the ligands, as well as the different spin mechanisms that take place in the cyanido ligands Spin-polarization on the carbon atoms and spin-delocalization on the nitrogen atoms. The results of our combined density functional theory (DFT) and multireference calculations were found in good agreement with the PND results and the experimental NMR chemical shifts. Moreover, the ab-initio calculations allowed us to connect the experimental spin-density map characterized by PND and the suggested distribution of the spin-density on the ligands observed by NMR spectroscopy. Interestingly, significant differences were observed between the pseudo-contact contributions of the chemical shifts obtained by theoretical calculations and the values derived from NMR spectroscopy using a simple point-dipole model. These discrepancies underline the limitation of the point-dipole model and the need for more elaborate approaches to break down the experimental pNMR chemical shifts into contact and pseudo-contact contributions.

Published
2019
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14. Probing the Local Magnetic Structure of the [Fe III (Tp)(CN) 3 ] − Building Block Via Solid‐State NMR Spectroscopy, Polarized Neutron Diffraction, and First‐Principle Calculations

Author

De, Siddhartha, primary, Flambard, Alexandrine, additional, Garnier, Delphine, additional, Herson, Patrick, additional, Köhler, Frank H., additional, Mondal, Abhishake, additional, Costuas, Karine, additional, Gillon, Béatrice, additional, Lescouëzec, Rodrigue, additional, Le Guennic, Boris, additional, and Gendron, Frédéric, additional

Published
2019
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16. Dimensionality switching through a thermally induced reversible single-crystal-to-single-crystal phase transition in a cyanide complex

Author

Gheorghe, Ruxandra, Kalisz, Marguerite, Clerac, Rodolphe, Mathoniere, Corine, Herson, Patrick, Yanling Li, Seuleiman, Mannan, Lescouezec, Rodrigue, Lloret, Francesc, and Julve, Miguel

Subjects
Cyanides -- Structure, Cyanides -- Chemical properties, Cyanides -- Thermal properties, Fourier transform infrared spectroscopy -- Usage, Iron -- Chemical properties, Manganese -- Chemical properties, Phase transformations (Statistical physics) -- Analysis, Pyrimidines -- Structure, Pyrimidines -- Chemical properties, Pyrimidines -- Thermal properties, X-ray crystallography -- Usage, Chemistry
Published
2010

17. Synthesis and Luminescence Properties of Cycloplatinated Complexes with a Chelating N ^\textrm∧ C Pyridine-Derived N-Heterocyclic Carbene - Influence of 2,4,6-Triphenyl­phosphinine versus Triphenylphosphine: Cycloplatinated N-Heterocyclic Carbene Complexes

Author

Moussa, Jamal, Freeman, Gemma R., Williams, J. A. Gareth, Chamoreau, Lise-Marie, Herson, Patrick, Amouri, Hani, Architectures Moléculaires (A.R.C), 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), Department of Chemistry [Durham, UK], Durham University, 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)-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), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience; no abstract

Published
2016
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18. Synthesis and characterization of Zr(IV) polyoxotungstates as molecular analogues of zirconia-supported tungsten catalysts

Author

Villanneau, Richard, Carabineiro, Hugo, Carrier, Xavier, Che, Michel, Thouvenot, Rene, Ribeiro, Fernando Ramoa, Herson, Patrick, and Lemos, Francisco

Subjects
Zirconium -- Chemical properties, Zirconium -- Research, Tungsten -- Chemical properties, Metal catalysts -- Analysis, Chemicals, plastics and rubber industries
Abstract

A new zirconium-containing polyoxotungstate was prepared by alkalinization of a solution of the monomeric form is studied. Its relevance to heterogeneous catalysis as molecular analogues of zirconia-supported tungsten catalysts is also discussed.

Published
2004

19. Probing the Local Magnetic Structure of the [FeIII(Tp)(CN)3]− Building Block Via Solid‐State NMR Spectroscopy, Polarized Neutron Diffraction, and First‐Principle Calculations.

Author

De, Siddhartha, Flambard, Alexandrine, Garnier, Delphine, Herson, Patrick, Köhler, Frank H., Mondal, Abhishake, Costuas, Karine, Gillon, Béatrice, Lescouëzec, Rodrigue, Le Guennic, Boris, and Gendron, Frédéric

Subjects
CHEMICAL shift (Nuclear magnetic resonance), NEUTRON diffraction, NUCLEAR magnetic resonance spectroscopy, MAGNETIC structure, AB-initio calculations, NUCLEAR magnetic resonance
Abstract

The local magnetic structure in the [FeIII(Tp)(CN)3]− building block was investigated by combining paramagnetic Nuclear Magnetic Resonance (pNMR) spectroscopy and polarized neutron diffraction (PND) with first‐principle calculations. The use of the pNMR and PND experimental techniques revealed the extension of spin‐density from the metal to the ligands, as well as the different spin mechanisms that take place in the cyanido ligands: Spin‐polarization on the carbon atoms and spin‐delocalization on the nitrogen atoms. The results of our combined density functional theory (DFT) and multireference calculations were found in good agreement with the PND results and the experimental NMR chemical shifts. Moreover, the ab‐initio calculations allowed us to connect the experimental spin‐density map characterized by PND and the suggested distribution of the spin‐density on the ligands observed by NMR spectroscopy. Interestingly, significant differences were observed between the pseudo‐contact contributions of the chemical shifts obtained by theoretical calculations and the values derived from NMR spectroscopy using a simple point‐dipole model. These discrepancies underline the limitation of the point‐dipole model and the need for more elaborate approaches to break down the experimental pNMR chemical shifts into contact and pseudo‐contact contributions. [ABSTRACT FROM AUTHOR]

Published
2019
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20. Synthesis, Crystal Structures, and Magnetic Properties of a New Family of Heterometallic Cyanide-Bridged Fe ^\textrmIII _\textrm2 M ^\textrmII _\textrm2 (M = Mn, Ni, and Co) Square Complexes

Author

Pardo, Emilio, Verdaguer, Michel, Herson, Patrick, Rousselière, Helene, Cano, Joan, Julve, Miguel, Lloret, Francesc, Lescouëzec, Rodrigue, Institut Parisien de Chimie Moléculaire (IPCM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Instituto de Ciencia Molecular (ICMol), and Universitat de València (UV)

Subjects
[CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2011
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22. Cationic Planar Chiral (η 6 -Arene)Mn(CO) 3 + Complexes: Resolution, NMR Study in Chiral-Oriented Solvents, and Applications to the Enantioselective Synthesis of 4-Substituted Cyclohexenones and (η6 -Phosphinoarene)Mn(CO)3+ Complexes

Author

Eloi, Antoine, Rose-Munch, Françoise, Rose, Eric, Pille, Ariane, Lesot, Philippe, Herson, Patrick, Université Pierre et Marie Curie - Paris 6 (UPMC), Institut Parisien de Chimie Moléculaire (IPCM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)

Subjects
PBLG, [CHIM.ORGA]Chemical Sciences/Organic chemistry, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Liquid crystals, Enantiodiscrimination, Polypeptide, Chiral complex, NMR
Abstract

International audience; An easy round-trip of (D)-(þ)-camphor enolate to a racemic mixture of cationic (η6-arene)Mn-(CO)3complexes is the base of the strategy adopted for the first resolution of such complexes. X-raystructures of one of the (η5-cyclohexadienyl)Mn(CO)3 diastereoisomers obtained after addition ofthe chiral auxiliary as well as of the corresponding enantiopure η6 cationic complex after rearomatizationhave been established. Proton-decoupled deuterium 2D NMR in chiral polypeptideliquid crystals proved to be an efficient tool for the determination of the enantiomeric purity of suchplanar chiral cationic η6 complexes. The potential of this unprecedented resolution is exemplified byenantioselective syntheses in organic and organometallic fields. Thus, starting from the enantiopure(η6-meta-halogenoanisole)Mn(CO)3 complexes, enantiopure 2,4-disubstituted cyclohexenoneswere easily generated through a Mn-assisted dearomatization process, and the first examples ofenantiopure η5- and η6-phosphino-substituted Mn complexes were obtained through lithiation/electrophilic quench sequence.

Published
2010
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23. Barium one-dimensional coordination polymers from barium β-diketonates and 2,2′-bipyrimidine derivatives

Author

Pointillart, Fabrice, Boubekeur, Kamal, Herson, Patrick, Train, Cyrille, Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Inorganique et Matériaux Moléculaires (CIM2), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire national des champs magnétiques intenses - Grenoble (LNCMI-G), Université Joseph Fourier - Grenoble 1 (UJF)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM.COOR]Chemical Sciences/Coordination chemistry, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2010

25. Synthesis and characterization of the first carbene derivative of a polyoxometalate

Author

Artero, Vincent, Proust, Anna, Herson, Patrick, Villain, Francoise, and Moulin, Christophe Cartier dit; Gouzerh, Pi

Subjects
Polymeric composites -- Research, Ruthenium -- Research, Ruthenium -- Chemical properties, Chemical compounds -- Research, Chemical compounds -- Chemical properties, Chemistry
Abstract

The synthesis and characterization of the first carbene derivative of polyoxometalate, [(PW9O34)(Sub 2)(cis-WO2)(cis-RuL(Sub 2)(Super Me)], (super -13) which displays an original molecular structure is presented. The study shows that the position of the rising edge is dependent on the oxidation state of ruthenium, and the higher the oxidation state, the higher its energy.

Published
2003

26. Framework Fluxionality of Organometallic Oxides : Synthesis, Crystal Structure, EXAFS, and DFT Studies on [{Ru(η6-arene)}4Mo4O16] Complexes

Author

Laurencin, Danielle, Fidalgo, Eva Garcia, Villanneau, Richard, Villain, Françoise, Herson, Patrick, Pacifico, Jessica, Stoeckli-Evans, Helen, Bénard, Marc, Rohmer, Marie-Madeleine, Süss-Fink, Georg, and Proust, Anna

Abstract

Reactions of the molybdates Na2MoO4•2 H2O and (nBu4N)2[Mo2O7] with [{Ru(arene)Cl2}2] (arene=C6H5CH3, 1,3,5-C6H3(CH3)3, 1,2,4,5-C6H2(CH3)4) in water or organic solvents led to formation of the triple-cubane organometallic oxides [{Ru(η6-arene)}4Mo4O16], whose crystal and molecular structures were determined. Refluxing triple cubane [{Ru(η6-C6H5CH3)}4Mo4O16] in methanol caused partial isomerization to the windmill form. The two isomers of [{Ru(η6-C6H5CH3)}4Mo4O16] were characterized by Raman and Mo K-edge X-ray absorption spectroscopy (XAS), both in the solid-state and in solution. This triple-cubane isomer was also used as a spectroscopic model to account for isomerization of the p-cymene windmill [{Ru(η6-1,4-CH3C6H4CH(CH3)2)}4Mo4O16] in solution. Using both Raman and XAS techniques, we were then able to determine the ratio between the windmill and triple-cubane isomers in dichloromethane and in chloroform. Density functional calculations on [{Ru(η6-arene)}4Mo4O16] (arene=C6H6, C6H5CH3, 1,3,5-C6H3(CH3)3, 1,4-CH3C6H4CH(CH3)2, C6(CH3)6) suggest that the windmill form is intrinsically more stable, provided the complexes are assumed to be isolated. Intramolecular electrostatic interactions and steric bulk induced by substituted arenes were found to modulate but not to reverse the energy difference between the isomers. The stability of the triple-cubane isomers should therefore be accounted for by effects of the surroundings that induce a shift in the energy balance between both forms.

Published
2006

27. Another Example of the Instability of a Keggin-Type Heteropolyanion in the Presence of Aqueous Hydrogen Peroxide: From [AsW12O40]3- to Low-Nuclearity Oxoperoxotungstates - Crystal Structure of [(nHex)4N]3[AsO4{W2O2(-O2)2(O2)2}2]

Author

Piquemal, Jean-Yves, Salles, Laurent, Chottard, Geneviève, Herson, Patrick, Ahcine, Chehrazed, Brégeault, Jean-Marie, Interfaces, Traitements, Organisation et Dynamique des Systèmes (ITODYS (UMR_7086)), Université Paris Diderot - Paris 7 (UPD7)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Systèmes interfaciaux à l'echelle nanometrique (SIEN), Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Inorganique et Matériaux Moléculaires (CIM2), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Université Pierre et Marie Curie - Paris 6 (UPMC)-ESPCI ParisTech-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)

Subjects
[CHIM.CATA]Chemical Sciences/Catalysis, Oxidation • Hydrogen peroxide • Peroxo ligands • Catalysis • Tungsten
Abstract

The Keggin dodecatungstoarsenato anion of HNa2[AsW12O40] is inherently unstable in aqueous hydrogen peroxide and is mainly degraded to [AsO4{W2O2(-O2)2(O2)2}2]3-, [HAsO4{W2O2(-O2)2(O2)2}]2- and [{WO(O2)2(H2O)}2(-O)]2-. These anions were isolated as salts and identified by elemental and spectroscopic analyses. The salt with the formula [(nC6H13)4]3[AsO4{W2O2(-O2)2(O2)2}2] was obtained from the reaction of tungstic acid, H2WO4 (or HNa2[AsW12O40]·nH2O), with aqueous hydrogen peroxide, HNa2[AsO4]·7H2O and [(nC6H13)4N]Cl. The structure was refined with R1 = 0.058 and wR2 = 0.067 [monoclinic C2 (no. 5); a = 20.516(6) Å, b = 15.923(4) Å, c = 14.902(2) Å, = 91.64(1)°, Z = 2]. The vibrational spectra (IR and Raman) suggest that the overall structure is maintained in organic solvents. The close relation between the phosphate- and arsenate-based complexes indicates that fluxional behaviour may exist for all these di- and tetranuclear complexes. Fluxionality may play a key role in the transfer of active oxygen (from peroxo groups) to organic substrates via {WO(O2)2} units. It is shown that the heteroligand [XOp]n- (X = As, HAs, MeAs, P, HP, etc.) has a marked effect on the stoichiometric and regioselective epoxidation of (R)-(+)-limonene to 1,2-epoxide at ambient temperature, for a given pH of the aqueous phase. The oxodiperoxo complexes can be used to carry out epoxidation stoichiometrically and regioselectively with (R)-(+)-limonene, but can also be employed in a catalytic process in a two-phase mixture at room temperature.

Published
2006

29. Vanadium-catalysed aerohic cleavage of C-C bond sin substituted cyclohexanones to afford carboxylic, acids. Two model complexes with tetrahedral geometry around vanadium (V)

Author

Vennat, Maxence, Herson, Patrick, Brégeault, Jean-Marie, Shul'Pin, Georgiy B., Systèmes interfaciaux à l'echelle nanometrique (SIEN), Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Inorganique et Matériaux Moléculaires (CIM2), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), N. N. Semenov Institute of Chemical Physics, and Russian Academy of Sciences [Moscow] (RAS)

Subjects
Catalysis • Oxidation • Dioxygen • Oxo ligands • Vanadium, [CHIM.CATA]Chemical Sciences/Catalysis
Abstract

Two monosilanol/disilanol derivatives were synthesised by treatment of Ph3SiOH or Ph2Si(OH)2 with [nBu4N]VO3 (3) in ethanol solution. The mononuclear anionic dioxo vanadium(V) species [{Ph3SiO}2VO2]- (4) and the dinuclear complex anion [{Ph2SiO2VO2}2]2- (5) thus obtained are unusual and novel model compounds with Si-O-V(O)2O linkages characterised by single-crystal X-ray diffraction. The catalytic activities of these tert-butylammonium complexes, together with those of the simple vanadium derivatives 3 and 5, of the vanadyl precursors VOSO4·5H2O (1) and [VO(acac)2] (2), and also of H6[PMo9V3O40]·aq, were tested for aerobic C-C bond cleavage in 2-hydroxycyclohexanone and 2-methylcyclohexanone. Monomeric vanadium species show the same chemistry as the polyoxometalate but with lower yields of acids or keto acids, and so the redox and acid properties of HPA-n (n = 3, 4) are better tuned. Mechanisms for these oxidation reaction, including electron transfer from a substrate coordinated to vanadium, are proposed.

Published
2003

47. Synthesis and Structure Activity Relationship of Organometallic Steroidal Androgen Derivatives

Author

Top, Siden, primary, Thibaudeau, Céline, additional, Vessières, Anne, additional, Brulé, Emilie, additional, Le Bideau, Franck, additional, Joerger, Jean-Michel, additional, Plamont, Marie-Aude, additional, Samreth, Soth, additional, Edgar, Alan, additional, Marrot, Jérôme, additional, Herson, Patrick, additional, and Jaouen, Gérard, additional

Published
2009
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