Browsing by Author "Prikhodchenko P."

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    Aqueous reduction of [Cp*2W2O5]: Characterization of the triangular clusters [Cp*3W 3O4(OH)2]2+ and [Cp* 3W3O6]+ - Comparison with molybdenum
    (Wiley-VCH Verlag, 2007) Dinoi C.; Sözen P.; Taban G.; Demir D.; Demirhan F.; Prikhodchenko P.; Gun J.; Lev O.; Daran J.-C.; Poli R.
    Zinc reduction of Cp*2W2O5 in an acidified water-methanol medium affords the green 3-electron trinuclear cluster [Cp*3W3O4(OH)2]2+, isolated and crystallographically characterized as the triflate salt, 1. Upon exposure to air, this complex is oxidized to a related 2-electron cluster, [Cp*3W3O6]+, which was crystallized and characterized in three different salts, 2-4. The 3-electron cluster exhibits a near-tetragonal frozen-glass EPR spectrum, and it shows evidence of coupling of the unpaired electron to only one of the three W atoms. The two-electron cluster is diamagnetic. An electrospray ionization MS n study revealed a stepwise expulsion of neutral [Cp*WO 2] units as the main fragmentation process. DFT calculations unveiled the intimate details of the electronic structures of these complexes and fully rationalized the structural and spectroscopic properties. © Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
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    Reduction of [Cp2*Mo2O5] by mercaptopropionic acid in an aqueous medium. Isolation and characterization of a dinuclear oxo- and 3-sulfido-proprionato(2-)-bridged molybdenum(IV) compound
    (2007) Dinoi C.; Prikhodchenko P.; Demirhan F.; Gun J.; Lev O.; Daran J.-C.; Poli R.
    Reaction of Cp2*Mo2O5 with HSCH2CH2COOH in acidic (by CF3COOH) 50:50 MeOH-H2O solvent at room temperature yields compound Cp2*Mo2(μ-O)(μ-SCH2CH2CO2)2, a dinuclear diamagnetic MoIV compound with a two-leg-sharing bis(four-legged piano stool) structure and a Mo-Mo distance of 2.6833(6) Å. A reaction monitoring by ESI MS shows the formation of an intermediate 18 mass units heavier, interpreted as a dihydroxo analogue. Electrochemistry shows a reversible, pH independent oxidation process and an irreversible, pH-dependent reduction process. Contrary to a recently published analogous reaction with the closely related HSCH2COOH substrate, this process does not lead to C-S bond cleavage. © 2007 Elsevier B.V. All rights reserved.