Benzenethiolato-derivatives of iridium(I) and iridium(III)

Abstract

The complexes trans-[IrX(CO)(PPh3)2](X = Cl, Br, or I) react with benzenethiol and pentafluorobenzenethiol to yield initially [IrHX(C6H5S)(CO)(PPh3)2] and [IrHX(C6F5S)(CO)(PPh3)2](2 isomers) respectively. Prolonged reaction with pentafluorobenzenethiol leads to a more complex mixture of products containing [IrHX2(CO)(PPh3)2], [IrH(C6F5S)2(CO)(PPh3)2], [IrHX(C6F5S)(CO)(PPh3)2], and [IrX3–n(C6F5S)n(CO)(PPh3)2](n= 0, 1 or 2). Related reactions with C6F4(SH)2 and C6H4(SH)(CO2H) are also reported. Metathetical displacement of chloride from trans-MCl(CO)(PPh3)2(M = Rh or Ir), by reaction with TlSC6F5, yields trans-[M(SC6F5)(CO)(PPh3)2], and the oxidative addition reactions of the latter complexes with X2, HX, HgX2, Mel, O2, H2, SO2, and C6F5SH have been investigated. The sulphur dioxide adduct, [Ir(SC6F5)(SO2)(CO)(PPh3)2] in the solid state or in solution reacts slowly with oxygen to yield the yellow sulphato-complex [Ir(SC6F5)(SO4)(CO)(PPh3)2]. This and several other similar conversions with related sulphur dioxide complexes have been followed gasometrically.