Cyclic carbonates synthesis by cycloaddition reaction of CO2 with epoxides in the presence of zinc-containing and ionic liquid catalysts

The current production of organic cyclic carbonates involves the reaction of appropriate alcohols with toxic phosgene. But an alternative route for obtaining these valuable products is the cycloaddition reaction of CO2 with appropriative epoxides. The development of new catalytic systems for this reaction is a highly active field of research works. For this purpose, were developed many effective catalytic systems, such as organocatalysts, metal–organic frameworks, homogeneous metal-based catalysts, and ionic liquid catalysts. Among them, zinc-containing and ionic liquid catalysts are highly active systems, resulting in the increase in selectivity and the beneficial effect on the reaction rate under mild reaction conditions: reaction temperatures of below 100 °C at a low CO2 concentration and pressure at 0.1 MPa, if possible, without solvents and co-catalysts. This review article summarizes and discusses the results of research works over the last 10–15 years on the study of the homogeneous zinc-containing and ionic liquid catalysts for the cycloaddition reaction of CO2 with epoxides. We hope that it can be stimulated for further development in this area and will be useful for understanding the potential commercialization of these catalysts.