Synthesis, structures and bonding of group 6 thio-complexes

Abstract

The structures and bonding of polythio complexes having group 6 metals are described. A trinuclear tungsten mixed valence complex, [{Cp*WCl(μ-S)2}2WO], 1 along with known [syn-(Cp*WS)2(µ-S)2] and [anti-(Cp*WS)2(µ-S)2] are synthesized by the thermolysis reaction of [Cp*WCl4] with [LiBH4·THF] followed by addition of 2-mercaptobenzothiazole (MBT-C7H5NS2). The electronic properties of these complexes associated with central metal atoms have been evaluated through UV–vis absorption spectra. Further, a η2-dithioacetate chromium complex, [Cp*Cr(CO)2(η2-S2CCH3)], 2 was synthesized by the reaction of [Cp*Cr(CO)3Me] with [LiBH4·THF] followed by the treatment of carbon disulfide (CS2). Both complexes 1 and 2 were characterized using multinuclear NMR, IR spectroscopy, mass spectrometry, as well as single-crystal X-ray diffraction. In addition, density functional theory (DFT) calculations were conducted to interpret and study the nature of bonding and electronic structures of 1 and 2.