A series of basic amino acids immobilized onto solid supports that can play cooperative
roles was developed and applied as environmentally benign catalytic systems for the
solventless synthesis of cyclic carbonates from epoxides and carbon dioxide under
metal-free and halide-free conditions. The highest yield of styrene carbonate was
achieved with silica supported l-histidine, associated with the acidic nature of silica: Si–OH groups on the silica
surface act as a weak acid to activate the epoxide for the synergetic effect with
the basic amino acid. The influence of various reaction parameters on catalytic activity
was investigated. Moreover, the catalyst exhibited good recyclability.
Key words
silica-supported amino acids - carbon dioxide - cyclic carbonate - epoxide - cycloaddition