Efficient fixation of CO2 into cyclic carbonate catalyzed by choline bromide/imidazole derivatives-based deep eutectic solvents

An efficient fixation of CO2 into cyclic carbonate catalyzed by imidazole-based deep eutectic solvents (DESs) was demonstrated. These DESs were composed of choline bromide (ChBr) and imidazole (Im) derivatives. Various epoxides bearing different groups were converted to the corresponding cyclic carbonates in remarkable yields under solvent-and additive-free conditions. Mechanistic studies suggested that the high catalytic activity of DESs is attributed to the synergistic catalysis between the HBAs and HBDs, and the active order of the characteristic functional groups in the HBAs is hydroxyl > carboxyl > ester group.

Automated summary

An efficient fixation of CO2 into cyclic carbonate catalyzed by imidazole-based deep eutectic solvents (DESs) was demonstrated. These DESs, composed of Choline Bromide (ChBr) and Imidazole (Im) derivatives, successfully converted various epoxides into cyclic carbonates under solvent-and additive-free conditions. Mechanistic studies revealed that the high catalytic activity of DESs is attributed to the synergistic catalysis between the HBAs and HBDs, with the hydroxyl group being the most active among the characteristic functional groups in the HBAs.