Synthesis and study of new N-heterocyclic carbene frameworks in the pursuit of durable, conductive organic and organometallic materials
A series of group 10 bis(benzimidazolylidene) complexes featuring chelating N- (o-phenol) moieties was synthesized and characterized. Based on these model systems, a new class of main-chain organometallic polymers comprised of a benzobis(imidazolylidene) ligand with chelating phenolate moieties and group 10 transition metals was synthesized and characterized. Also, a new N-heterocyclic carbine architecture comprising a 1,4-naphthoquinone annulated to 1,3-dimesitylimidazolylidene (NpQ-NHC) was synthesized. The free NpQ-NHC was characterized and was used to synthesize various Rh and Ag complexes that ranged in [pi]-electron density. The [pi]- systems of these complexes were analyzed using infrared spectroscopy and cyclic voltammetry. In contrast to previous reports, [pi]-backbonding was found to be non-negligible and was directly influenced by the metal's electronic character.