Complexes derived from the reactions of diphenylphosphinoacetic acid. Part 4. Mononuclear complexes of Rh(I), Ir(I) and Ir(III) and some related chemistry involving the diphenyl(2,6-dimethylphenyl)-phosphine ligand

Article abstract of DOI:10.1016/S0020-1693(02)01190-8

The iridium complex [IrCl(COD)]₂ reacts with diphenylphosphinoacetic acid (1) in the presence of CO to afford the iridium(III) complex IrHCl(CO)(η²-Ph₂PCH₂CO₂) (η¹-Ph₂PCH₂CO₂H) (3) which in the solid state exists as a hydrogen-bonded dimer. Complex 3 converts to IrH(CO)(η²-Ph₂PCH₂CO₂) ₂ (4) when treated with AgO₃SCF₃ in dichloromethane. The tertiary phosphine PPh₂(Ph-2,6-Me₂) (2) reacts with solutions of [RhCl(CO)₂]₂ and [IrCl(COD)]₂ (in the presence of CO) in dichloromethane to give the square planar complexes MCl(CO)[PPh₂(Ph-2,6-Me₂)]₂ (M=Rh (5) or Ir (6)) in high yield. While the iridium(I) complex 6 undergoes an oxidative-addition reaction with HgCl₂ to yield the complex IrCl₂(HgCl)(CO)[PPh₂(Ph-2,6-Me₂)] ₂ (7), complex 5 is unreactive towards this reagent.