Synthesis and structural characterization of a binuclear iridium complex with bridging, bidentate N-heterocyclic carbene coordination of 2,2':6',2''-terpyridine.

Thermal activation of terpyridine in the presence of an unsaturated Ir(III) fragment stabilized by a hydrotris(pyrazolyl) borate ligand gives rise to mononuclear complex and binuclear , in which the polypyridine behaves, respectively, as a mono- or a bi-dentate N-heterocyclic carbene.