In this project in the Inorganic, Bioinorganic, and Organometallic Program, Dr. T. Don Tilley of the University of California at San Diego will prepare transition metal complexes containing reactive silicon species. Transition metal complexes are known to act as catalysts for reactions of silicon compounds and may serve as catalysts for the preparation of silicon-containing polymers. These polymers could have structural and electronic properties useful in diverse applications. By analogy to studies of carbenes (important in polymer formation in hydrocarbons), Tilley will prepare complexes to help eludicate the chemical properties of silicon-containing fragments in the coordination sphere of transition metals. Complexes of silylenes, silenes, and disilenes which could serve as intermediates in new synthetic methods for monomeric and polymeric silicon compounds will be prepared. For example, silylene complexes may be intermediates in metal-catalyzed Si-Si bond formation in polysilane polymers. Modes of silicon activation by transition metals will be studied by acquiring mechanistic information on formation of eta-2-silane complexes, migration of silyl groups to a metal center, and dehyrogenative silane coupling. Among the metals used will be Ru, Pt, Rh, Ir, W, Os, and Mo.
