SYNTHESIS AND CHARACTERIZATION OF MOLYBDENUM(VI)-DIOXO COMPLEXES CONTAINING BOTH COORDINATED THIOLATE AND CARBOXYLATE GROUPS - REACTIONS WITH THEIR OWN FREE LIGANDS

The synthesis, characterization and spectroscopic properties of a grou p of Mo(VI) complexes having thiocarboxylate ligands of type [(MoO2)-O -VI(O2CC(S)MePh-X)(2)](2-) have been reported (X = H,p-Me,p-Cl). The p eak potential for the Mo(VI) reduction increases according to the elec tron-donor ability of X (Me > H > Cl), Reaction of these Mo(VI) comple xes with their own free ligands has been studied by ESR and UV-Vis spe ctroscopy, yielding the monomeric [(MoO)-O-V(O2CC(S)MePh-X)(2)](-) as unique complex products. The kinetic study of this oxidation reaction has also been investigated. (C) 1998 Elsevier Science S.A.