Members of the series IrX(CO)(PPh3)2 with various anionic ligands and their dioxygen complexes

Abstract

Acetonitrile is displaced from [Ir(CO)(CH₃CN)(PPh₃)₂]⁺ by the co-ordinating anions, F^–, OH^–, NCO^–, NCS^–, O₂CH^–, O₂CCF₃^–, SH^–, CCPh^–,P-toluenesulphinate, and CN^– to yield four-co-ordinate analogues of IrCl(CO)-(PPh₃)₂ except for the cyanide which is five-co-ordinate, IrCN (CO)(PPh₃)₃. The comparative uptake of dioxygen by these compounds to form dioxygen complexes has been studied. The sulphinate, Ir(P-toluenesulphinate)-(CO)(PPh₃)₂is O-bound but upon further co-ordination of CO or O₂ the sulphinate changes to S-bound although addition of methyl iodide produces an O-bound iridum(III) compound.