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  • Publication
    Accès libre
    Hydrogen-bonded systems between monocarboxylic acids and the trinuclear cluster cation [H3Ru3(C6H6)(C6Me6)2(O)]+ : cold-spray ionisation mass spectroscopic and X-ray crystallographic studies
    (2004-09-01) ;
    Vieille-Petit, Ludovic
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    Sei, Yoshihisa
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    Yamaguchi, Kentaro
    The hydrogen-bonded systems formed between monocarboxylic acid derivatives and the trinuclear arene-ruthenium cluster cation [H3Ru3(C6H6)(C6Me6)2(O)]+ (1) have been studied in solution by cold-spray ionisation mass spectroscopy (CSI-MS) and in the solid state by single-crystal X-ray structure analysis of the tetrafluoroborate salts. The presence of 1:1 (acid:cluster) adducts in acetone solution has been clearly demonstrated by CSI-MS. Single-crystal X-ray structure analyses of selected acid-cluster complexes show that in every case the hydroxyl of the acid function interacts strongly with the μ3-oxo ligand of cation 1, the O O distance ranging from 2.499(9) to 2.595(11) Å.
  • Publication
    Accès libre
    Ruthenium(II) complexes with ferrocene-modified arene ligands: synthesis and electrochemistry
    (2004) ;
    Vieille-Petit, Ludovic
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    Jeanneret-Gris, Julie
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    Štěpnička, Petr
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    A series of arene–ruthenium complexes of the general formula [RuCl26-C6H5 (CH2)2R}L] with R=OH, CH2OH, OC(O)Fc, CH2OC(O)Fc (Fc=ferrocenyl) and L=PPh3, (diphenylphosphino)ferrocene, or bridging 1,1′-bis(diphenylphosphino)ferrocene, have been synthesized. Two synthetic pathways have been used for these ferrocene-modified arene–ruthenium complexes: (a) esterification of ferrocene carboxylic acid with 2-(cyclohexa-1,4-dienyl)ethanol, followed by condensation with RuCl3nH2O to afford [RuCl26-C6H5 (CH2)2OC(O)Fc}]2, and (b) esterification between ferrocene carboxylic acid and [RuCl26-C6H5 (CH2)3OH}L] to give [RuCl26-C6H5 (CH2)3OC(O)Fc}L]. All new compounds have been characterized by NMR and IR spectroscopy as well as by mass spectrometry. The single-crystal X-ray structure analysis of [RuCl26-C6H5 (CH2)3OH}(PPh3)] shows that the presence of a CH2CH2CH2OH side-arm allows [RuCl26-C6H5 (CH2)3OH}(PPh3)] to form an intramolecular hydrogen bond with a chlorine atom. The electrochemical behavior of selected representative compounds has been studied. Complexes with ferrocenylated side arms display the expected cyclic voltammograms, two independent reversible one-electron waves of the Ru(II)/Ru(III) and Fe(II)/Fe(III) redox couples. Introduction of a ferrocenylphosphine onto the ruthenium is reflected by an additonal reversible, one-electron wave due to ferrocene/ferrocenium system which is, however, coupled with the Ru(II)/Ru(III) redox system.
  • Publication
    Accès libre
    An asymmetric trihydrido-bridged arene ruthenium complex
    (2004)
    Vieille-Petit, Ludovic
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    ;
    Reaction of [Ru(η6-indane)(H2O)3]2+ and [Ru(η6-C6Me6)(H2O)3]2+ with NaBH4 in water gives a mixture of three triple hydrido-bridged arene ruthenium cations [(η6-arene)Ru(μ-H)3Ru(η6-arene′)]+ (arene=indane and hexamethylbenzene; arene′=indane and hexamethylbenzene). After treatment with NaBF4, the three complexes are separated by column chromatography and the asymmetrical [(η6-indane)Ru(μ-H)3Ru(η6-C6Me6)][BF4] (cation 1a) can be isolated in moderate yield. 1a decomposes in solution to give the corresponding hydroxo-bridged complex [(η6-indane)Ru(μ-OH)3Ru(η6-C6Me6)]+ (2) with retention of the asymmetrical geometry as shown by single-crystal X-ray structure analysis. The indane ligand adopts an envelope conformation toward the ruthenium atom.
  • Publication
    Accès libre
    endo and exo Coordination of Indanol: Synthesis, Isolation and Structural Characterisation of [H3Ru3 (endo-Indanol)(C6Me6)2(O)]+ and [H3Ru3 (exo-Indanol)(C6Me6)2 (O)]+ as Their Tetrafluoroborate Salts
    (2004)
    Vieille-Petit, Ludovic
    ;
    Karmazin-Brelot, Lydia
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    Labat, Gael
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    The reaction of 2,3,4,7-tetrahydro-1H-inden-2-ol with ruthenium chloride hydrate in refluxing ethanol yields the chloro-bridged dinuclear complex [RuCl2(indanol)]2 (1). The mononuclear complex [Ru(indanol)(H2O)3]2+ (2), formed in situ from 1 in aqueous solution, reacts with the dinuclear complex [H3Ru2(C6Me6)2]+ to give a trinuclear arene-ruthenium cluster as a mixture of two isomers, the cations [H3Ru3(endo-indanol)(C6Me6)2(O)]+ (3a) and [H3Ru3(exo-indanol)(C6Me6)2(O)]+ (3b), in a 1:1 ratio. The hydroxy function of the indanol ligand is oriented towards the μ3-oxo cap of 3a, whereas the OH group is bent away from the metal skeleton of 3b. These two isomers, which can easily be separated by silica-gel chromatography, were isolated and characterised as their tetrafluoroborate salts. The single-crystal X-ray structure analysis of [3a][BF4] shows a strong intramolecular hydrogen bond between the μ3-oxo ligand and the hydroxyl function, which even persists in acetone solution, as demonstrated by NMR spectroscopy. On the other hand, the hydroxy function of 3b was found to be free in the solid state as well as in solution, as shown by an X-ray crystal structure analysis and by NMR spectroscopy. The catalytic activities of the water-soluble trinuclear cations 3a and 3b for the hydrogenation of benzene to give cyclohexane under biphasic conditions are considerably different, the exo isomer 3b being more active than the endo isomer 3a.
  • Publication
    Accès libre
    Synthesis of a trinuclear cation [H3Ru3(Fc-arene)(C6Me6)2(O)]+ containing a ferrocenyl group tethered to an arene ligand
    (2003-11-20)
    Vieille-Petit, Ludovic
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    Unternährer, Sabine
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    ;
    Ferrocene carboxylic acid 2-cyclohexa-1,4-dienyl-ethyl ester (1) is prepared from ferrocene carboxylic acid and 2-cyclohexa-1,4-dienyl-ethanol. This diene reacts with RuCl3nH2O in refluxing ethanol to afford quantitatively [Ru(Fc-arene)Cl2]2 (2) (Fc-arene=ferrocene carboxylic acid phenethyl ester). The dinuclear complex 2 reacts with triphenylphosphine to give the mononuclear complex [Ru(Fc-arene)(PPh3)Cl2] (3). The trinuclear arene-ruthenium cluster cation [H3Ru3 (Fc-arene)(C6Me6)2(O)]+ (4) is synthesised from the dinuclear precursor [H3Ru2 (C6Me6)2]+ and the mononuclear complex [Ru(Fc-arene)(H2O)3]2+, accessible from 2 in aqueous solution. The water-soluble trinuclear cluster cation 4 catalyses the hydrogenation of benzene to give cyclohexane under biphasic conditions.
  • Publication
    Accès libre
    Chiral Arene Ruthenium Complexes : Synthesis and Molecular Structure of the Enantiopure Cluster Cation (S)-[H3Ru3{C6H5[CH(CH3)CH2OH]}(C6Me6)2(O)]+
    (2003)
    Vieille-Petit, Ludovic
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    ;
    The reaction of enantiopure (R)-(2-cyclohexa-1,4-dienyl)propan-1-ol with ruthenium chloride hydrate yields, without racemisation of the chiral ligand, the chloro-bridged dinuclear complex (S,S)-[RuCl2{C6H5[CH(CH3)CH2OH]}]2 (1). The dimer 1 reacts with triphenylphosphane to give the mononuclear complex (S)-[RuCl2{C6H5[CH(CH3)CH2OH]}(PPh3)] (2). A single-crystal X-ray structure analysis of 2 reveals the absolute configuration of the asymmetric carbon atom to have remained, the change from (R) to (S) being due to the priority change caused by coordination; in the solid state, onedimensional hydrogen-bonded chains are formed between the hydroxy functions and chloro ligands of neighbouring molecules. The mononuclear cationic complex (S)-[Ru{C6H5[CH(CH3)CH2OH]}(H2O)3]2+, formed in situ from 1 in aqueous solution, reacts with the dinuclear complex [H3Ru2(C6Me6)2]+ to give a chiral trinuclear arene-ruthenium cluster, the cation (S)-[H3Ru3{C6H5[CH(CH3)CH2OH]} (C6Me6)2(O)]+ (3). This enantiopure cation has been isolated and characterised as its tetrafluoroborate salt. The single-crystal X-ray structure analysis of (S)-[3][BF4] shows a strong intramolecular hydrogen bond between the μ3-oxo cap and the hydroxy function, which also persists in acetone solvent, as demonstrated by NMR spectroscopy.