An iridium(III/IV/V) redox series featuring a terminal imido complex with triplet ground state

The iridium(iii/iv/v) imido redox series [Ir(NtBu){N(CHCHPtBu2)(2)}](0/+/2+) was synthesized and examined spectroscopically, magnetically, crystallographically and computationally. The monocationic iridium(iv) imide exhibits an electronic doublet ground state with considerable imidyl' character as a result of covalent Ir-NtBu bonding. Reduction gives the neutral imide [Ir(NtBu){N(CHCHPtBu2)(2)}] as the first example of an iridium complex with a triplet ground state. Its reactivity with respect to nitrene transfer to selected electrophiles (CO2) and nucleophiles (PMe3), respectively, is reported.