Reactions of low-valent metal complexes with fluorocarbons. Part XI. Chlorocarbonylbis(methyldiphenylphosphine)iridium and chlorodinitrogenbis(triphenylphosphine)iridium

Abstract

Chlorocarbonylbis (methyldiphenylphosphine)iridium forms a stable 1 : 1 adduct with tetrafluoroethylene in which it is proposed the phosphine ligands have a relative cis-configuration. An analogous reaction occurs with 1,2-dichloro-1,2-difluoroethylene, whereas hexafluorobut-2-yne reacts to give a mixture of (Ph₂PMe)₂lr(CO)Cl(CF₃C₂CF₃) and (Ph₂PMe)₂lr(CO)Cl(CF₃C₂CF₃)₂. In both complexes the phosphines have a relative trans-configuration. Tetrafluoroethylene displaces nitrogen from (Ph₃P)₂lr(N₂)Cl to give the co-ordinatively unsaturated complex (Ph₃P)₂lr(C₂F₄)Cl, which readily reacts with triphenylphosphine to give (Ph₃P)₃lr(C₂F₄)Cl. The nitrogen complex reacts with hexafluorobut-2-yne to give (Ph₃P)₂lr(CF₃C₂CF₃)Cl; which with triphenylphosphine affords (Ph₃P)₃lr(CF₃C₂CF₃)Cl; and with but-2-yne gives the iridocyclopentadiene (Ph₃P)₂lrCl[(CF₃)₂C₂·C₂(CH₃)₂]. The tetrafluoroethylene and monoacetylenic iridium complexes both give (Ph₃P)₂lr(CO)Cl when heated with water.