Organometallic chemistry and homogeneous catalysis of Rh and Rh-Co mixed metal carbonyl clusters

The reactions of hydrosilane and/or alkyne as well as isonitriles with rhodium and rhodium cobalt mixed metal carbonyl clusters, e.g., Rh4(CO)12 and Co2Rh2(CO)12, are studied. Novel mixed metal complexes, e.g., CoRh(CO)5 (HC≡CBu n ), (R3Si)2Rh(CO) n Co(CO)4, Rh(R−N≡C)4Co(CO)4, Co2Rh2(CO)10(HC≡CR), and Co2Rh2(CO)9(HC≡CBu n ), are synthesized and identified. The catalytic activities of these rhodium and rhodium-cobalt mixed metal complexes are examined in hydrosilyation, silylformylation, and novel silylcarbocyclization reactions. Possible mechanisms for these reactions are proposed and discussed.