Hydride-phosphoniodithiocarboxylate Phosphonium-betaine Isomerism in Cy₃PCS₂ Complexes of Ruthenium

Abstract

Reaction of Cy3PCS2 (Cy = cyclohexyl) with the hydrido complexes [RuClH(CA)(PPh3)3] (A = O, S), [RuH(CO)(NCMe)2(PPh3)2]+, and [RuH(OClO3)(CO)(CN(t)Bu)(PPh3)2] leads to the complex cations [RuH(CA)(PPh3)2(eta2-S2CPCY3)]+, [RU(eta2-S2CHPCY3)(CO) (PPh3)2]+, [RuH(eta1-S2CPCY3)(CO)(CN(t)Bu)(PPh3)2]+. The sigma-vinyl complex [Ru(CH=CHC6H4Me-4)Cl(CO)(PPh3)2] reacts with Cy3PCS2 to give the cationic complex [Ru(CH=CHC6H4Me-4) (CO)(PPh3)2(eta2-S2CPCy3)]+, but this complex is not formed by hydroruthenation of HC=CC6H4Me-4 by [RuH(CO)(PPh3)2(eta2-S2CPCy3)]+. The inter-relationships between the above complexes are discussed.