The interaction of hydridocarbonyltris(triphenylphosphine) complexes of iridium(I) and rhodium(I) with alk-1-ynes

The acetylide complexes M(CCR)(CO)(PPh3)3 and M(CCR)(CO)(PPh3)2(M = Ir, Rh; R = alkyl or substituted alkyl), have been prepared by direct interaction of alk-1-ynes with MH(CO)(PPh3)3 and IrH(CO)2(PPh3)2. The bis- and tris-triphenylphosphine species exist in equilibrium in solution and undergo a wide range of oxidative addition reactions and additions of neutral ligands. Displacement of the acetylide group by more activated acetyl-enes, e.g., PhCCH, has been demonstrated. The complexes act as catalysts for the polymerisation of such acetylenes and of acetylene gas.