Efficient and Convenient Transformation of CO 2 into α‑Alkylidene Cyclic Carbonates over Reusable and Heterogeneous Cu-MCM-41 Supported Ionic Liquid Catalyst

The efficient conversion of CO 2 into value-added chemicals is of great importance. Herein, a type of transition metal-doped MCM-41 supported ionic liquids were synthesized, and efficiently used as catalysts for the effective carboxylative cyclization of propargylic alcohols and CO 2 into α-alkylidene cyclic carbonates. The supported catalyst Cu-MCM-41@ILTiCl 5 with a synergistic effect between the active copper sites and the anion could efficiently promote the carboxylative cyclization of propargylic alcohols and CO 2 in high to excellent yields. After the reaction, the catalyst could be easily separated from the reaction mixture by simple centrifugation, and then reused for six times without noticeable decrease in the catalytic activity.These findings may be useful for the rational design of novel highly active and efficient catalysts for the transformation of CO 2 into value-added α-alkylidene cyclic carbonates. Graphical Abstract An efficient protocol has been developed for producingα-alkylidene cyclic carbonates in excellent yields under cocatalyst- and solvent-free conditions by treating propargylic alcohols with carbon dioxide, promoted by Cu-MCM-41 supported ionic liquid catalyst.