Oxidative addition reactions of an iridium(I) complex containing phosphine-NHC

Abstract The phosphane functionalized N-heterocyclic carbene ligand 3-[2-(diphenylphosphino)ethyl]-1-ethylimidazol-2-ylidene was reacted with the [Ir(COD)Cl]2 metal precursor to give the homoleptic mononuclear cationic complex [Ir(NHC-PPh2)2][PF6] 2a in good yield. 2a undergoes oxidative addition and addition reactions with small molecules like H2, O2, S8, I2, CH3I and CO to afford the novel Ir(III) complexes [Ir(H)2(NHC-PPh2)2][PF6] 3a, [Ir(η2-O2)(NHC-PPh2)2][PF6] 4a, [Ir(η2-S2)(NHC-PPh2)2][PF6] 5a, [Ir(I)2(NHC-PPh2)2][I3] 6a, [Ir(CH3)(I)(NHC-PPh2)2][I] 7a, and [Ir(CO)(NHC-PPh2)2][PF6] 8a, respectively. All the new Ir(I) and Ir(III) complexes have been characterised by 31P, 1H and 13C NMR spectroscopy and single-crystal X-ray analysis.