A non-oxo methanolate-bridged divanadium(IV) complex with tris(2-sulfanidylphenyl)phosphane ligands: synthesis, structural characterization and magnetic investigation

Vanadium chemistry is of interest due its biological relevance and medical applications. In particular, the interactions of high-valent vanadium ions with sulfur-containing biologically important molecules, such as cysteine and glutathione, might be related to the redox conversion of vanadium in ascidians, the function of amavadin (a vanadium-containing anion) and the antidiabetic behaviour of vanadium compounds. A mechanistic understanding of these aspects is important. In an effort to investigate high-valent vanadium–sulfur chemistry, we have synthesized and characterized the non-oxo divanadium(IV) complex salt tetraphenylphosphonium tri-μ-methanolato-κ6O:O-bis({tris[2-sulfanidyl-3-(trimethylsilyl)phenyl]phosphane-κ4P,S,S′,S′′}vanadium(IV)) methanol disolvate, (C24H20P)[VIV2(μ-OCH3)3(C27H36PS3)2]·2CH3OH. Two VIVmetal centres are bridged by three methanolate ligands, giving aC2-symmetric V2(μ-OMe)3core structure. Each VIVcentre adopts a monocapped trigonal antiprismatic geometry, with the P atom situated in the capping position and the three S atoms and three O atoms forming two triangular faces of the trigonal antiprism. The magnetic data indicate a paramagnetic nature of the salt, with anS = 1 spin state.