Halogen-free fixation of carbon dioxide into cyclic carbonates via bifunctional organocatalysts

Bifunctional organocatalysts bearing diamine and carboxylic acid groups were used for the preparation of cyclic carbonates by cycloaddition reactions of CO2 and epoxides. Hydrogen-bonding interactions originating from carboxylic acids are of enormous importance due to their contribution in enabling the opening of the epoxide ring. In addition, the diamine can activate the CO(2)via carbamate formation and accelerate its transformation to cyclic carbonates. As a result of this synergy, this metal-free system shows excellent catalytic activities with high yields (92-99%) and selectivities (99%), and thus, provides a promising halogen-free and green pathway for the synthesis of cyclic carbonates from CO2 and epoxides.

Automated summary

Bifunctional organocatalysts with diamine and carboxylic acid groups were used to prepare cyclic carbonates through cycloaddition reactions, showing excellent catalytic activities with high yields and selectivities. This metal-free system provides a promising halogen-free and green pathway for the synthesis of cyclic carbonates from CO2 and epoxides.