Dwight D. Heinrich

RECENT DEVELOPMENTS IN VANADIUM SULPHUR AND OXYGEN CHEMISTRY

Abstract We survey recent results from our efforts in vanadium sulphur and oxygen chemistry. A unifying theme for most of the discussion is the reactivity characteristics of vanadyl (VO 2+ ) complexes, and it is shown how such complexes are capable of a variety of transformations leading to products with oxidation states in the range III–V and nuclearities in the range 1–5. Also described are mononuclear non-oxo vanadium sulphur complexes, including the structural characterization of both V(SBu t ) 4 and V(SBu t ) 4 − . The relevance of this work to our understanding of the fate of crude oil vanadyl impurities during hydrotreating processes is discussed.

Synthesis of tetranuclear and pentanuclear vanadium-oxide-carboxylate aggregates

Treatment of VOCl42– with tca–(tca–= thiophene-2-carboxylate) under aerobic conditions leads to formation of [V5O9Cl(tca)4]2–, whereas if AgNO3 is also present, the product is [V4O8(NO3)(tca)4]2–; the two anions have been isolated as NR4+ salts and their unusual structures elucidated by crystallographic methods.

Synthesis and structure of [Au(CH2)2PPh2]2[SSC(NPh)(NHPh)]2,a gold(II) ylide dimer containing the first example of a sulphur-rich thiourea

The reaction of SC(NHPh)2 with [Au(CH2)2PPh2]2Cl2 followed by addition of base has led to the isolation and X-ray crystal structure analysis of a gold(II) ylide dimer, [Au(CH2)2PPH2]2[SSC(NPh)(NHPh)]2 which is the first example of a thiourea containing catenated disulphide co-ordinated to a metal centre.