Discrete metal-based catalysts for the copolymerization CO2 and epoxides:: Discovery, reactivity, optimization, and mechanism

Most synthetic polymers are made from petroleum feedstocks. Given the non-renewable nature of these materials, there is increasing interest in developing routes to polymeric materials from renewable resources. In addition, there is a growing demand for biodegradable polymeric materials. Polycarbonates made from CO2 and epoxides have the potential to meet these goals. Since the discovery of catalysts for the copolymerization of CO2 and epoxides in the late 1960's by Inoue, a significant amount of research has been directed toward the development of catalysts of improved activity and selectivity. Reviewed here are well-defined catalysts for epoxide-CO2 copolymerization and related reactions.