A high-yield synthetic approach to trans-[Ir(ER 3) 2(CO)X] (ER 3=PMe 3, PEt 3, PPhMe 2, PPh 2Me, P(OMe) 3, AsMe 3, AsEt 3, AsPh 3, SbPh 3; X=Cl, Br)

Abstract

The complex [Ir(CO) 2X 2][NBu 4] (X=Cl, Br) forms Vaska-type complexes, trans-[Ir(ER 3) 2(CO)X], when treated with two equivalents of aryl- or alkyl-phosphines, arsines, or stibines under a CO atmosphere. The synthesis is general for a wide range of phosphines, arsines, or stibines irrespective of the cone angle. For small cone-angle ligands, the initial addition of ligand to [Ir(CO) 2X 2][NBu 4] is performed at low temperature. The synthesis and characterisation of three new Vaska-type complexes trans-[Ir(P(OMe) 3) 2(CO)Cl], trans-[Ir(AsMe 3) 2(CO)Cl], and trans-[Ir(AsEt 3) 2(CO)Cl] is also reported.