C-C bond-forming reactions of Ir(III)-alkenyls and nitriles or aldehydes: generation of reactive hydride- and alkyl-alkylidene compounds and observation of a reversible 1, 2-H shift in stable hydride-Ir(III) alkylidene complexes.

Nucleophilic attack of the beta-carbon of an Ir(III)-alkenyl functionality onto the alpha-carbon of a coordinated nitrile- or aldehyde occurs intramoleculary to yield initially iridacyclic structures. Nitriles give rise to isolable complexes that contain delocalized five-membered rings (iridapyrroles, e.g.