One-Pot Synthesis of Organic Carbonate from Alcohol and Alkyl Bromide under Low CO2 Pressure

A mild and highly efficient approach has been developed for the one-pot synthesis of organic carbonate from CO2, alcohol and alkyl bromide using 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as the activator. The conditions of template reaction were screened and the corresponding product butyl methyl carbonate (BMC, 1), was obtained with a high yield of 95 % in 1 h. The reaction system can be extended for the synthesis of organic carbonates from a broad range of alcohols and alkyl bromides with excellent yields under low CO2 pressure. DBU was proved to be recyclable after having been treated with KOH in ethanol. In addition, a plausible mechanism of this reaction was proposed according to the present results and literature reports.