Browsing by Author "Baya M."

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    Reduction of [Cp2*Mo2O5] by thioglycolic acid in an aqueous medium: Synthesis and structure of [{Cp*Mo(μ-SCH2COO)}2(μ-S)]
    (2006) Demirhan F.; Taban G.; Baya M.; Dinoi C.; Daran J.-C.; Poli R.
    Compound [Cp2*Mo2O5] reacts with thioglycolic acid, HSCH2COOH, in an acidic (CF3COOH) mixed water-methanol solvent, to yield compound [{Cp*Mo(μ-SCH 2CO2)}2(μ-S)]. During this reaction, the thioglycolic acid acts as a reducing agent, as a ligand, and provides a sulfide ion for the Mo-S-Mo bridge. The molecular structure of the product can be described as containing two four-legged piano stools that share three legs. The Mo-Mo distance of 2.792(7) Å indicates metal-metal bonding, in agreement with the compound diamagnetism. © 2005 Elsevier B.V. All rights reserved.
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    Reduction of [Cp*2Mo2O5] in aqueous medium: Structure and properties of a triangular mixed oxo-hydroxo-bridged product, [Cp*3Mo3(μ-O)2(μ-OH) 4](X)2 (X = CF3CO2 or CF 3SO3)
    (Wiley-VCH Verlag, 2006) Demirhan F.; Çaǧatay B.; Demir D.; Baya M.; Daran J.-C.; Poli R.
    The reduction of [Cp*2Mo2O5] with Zn in a MeOH/H2O solution acidified with either CF3COOH or CF3SO3H leads to the formation of the [Cp* 3Mo3(μ-O)2(μ-OH)4] 2+ ion as its trifluoroacetate or trifluoromethanesulfonate salt. The structure of the compound was confirmed by X-ray analyses. The anions establish hydrogen-bonding interactions with all four bridging OH groups. Density functional calculations afford bonding parameters in close agreement with the observed structure and indicate that the cluster is best described as a valence-delocalized Mo313+ species. The five metal electrons are distributed among an α-type (z2) orbital, which accounts for most of the metal-metal attraction, and two essentially metal-metal nonbonding e-type (xy) orbitals with a slight Mo(μ-O) π*-type contribution. Because of the C2 symmetry, the latter orbitals are not degenerate. The calculations show that the unpaired electron is located in a molecular orbital with equal contribution from two Mo atoms, in agreement with the experimental observation of coupling of the unpaired electron to two Mo atoms in the isotropic EPR spectrum. © Wiley-VCH Verlag GmbH & Co. KGaA, 2006.