Highly efficient synthesis of unsymmetrical organic carbonates from alcohols and diethyl carbonate over mesoporous carbon-supported MgO catalysts

Transesterification of dialkyl carbonate with various alcohols is a very attractive route for synthesizing unsymmetrical organic carbonates. Intensive efforts have been focused on developing highly active and stable heterogeneous catalysts that can efficiently catalyze the transesterification reaction at mild conditions. In this work, the synthesis of unsymmetrical organic carbonates was conducted over a series of mesoporous carbon-supported MgO (MgO/MC) catalysts. The composition-optimized MgO/MC catalyst exhibited remarkably high activity, selectivity and stability for the transesterification of diethyl carbonates with various alcohols at the commonly used reaction temperature of 125 °C, and could even work well at ambient temperature. The uniformly dispersed MgO species should be the main active sites for the transesterification reaction, while the neighboring oxygen- and nitrogen-containing groups existed on the surface of MC support may also play positive role in synergistically activating the reagents, thus leading to efficient production of the corresponding unsymmetrical organic carbonates at very mild conditions.