Reactivity studies of a pseudo three-coordinate vanadium(II) complex: Synthesis of terminal oxo and sulfido complexes of vanadium(IV) and S-S and Se-Se reductive bond cleavage reactions

Terminal oxo and sulfido complexes in the form of (nacnac)V=E(Ntol(2)) (nacnac = [ArNC(CH3)](2)CH , Ar = 2,6-(CHMe2)(2)C6H3, Ntol(2) = N(C6H4-4-Me), E = O (1), S (2)) were isolated from treatment of the masked three-coordinate vanadium(II) complex, (nacnac)V(Ntol(2)), with C5H5NO and S-8, respectively. Both vanadium(IV) species, 1 and 2, have been characterized by room temperature X-band EPR spectroscopic studies, and in the case of complex 1, a single crystal molecular structure confirmed the presence of a terminal oxo moiety. Moreover, reaction of (nacnac)V(Ntol(2)) with diphenyl-disulfide and diphenyldiselenide results in the reductive cleavage of these compounds to produce the vanadium(III) complexes (nacnac)V(XPh)(Ntol(2)) (X = S, (3), Se (4)). A molecular structure of the phenylsulfide complex, 3, confirmed formation of the d(2) complex resulting from reductive cleavage of the S-S bond. (C) 2010 Elsevier B. V. All rights reserved.