Efficient fixation of CO2 into cyclic carbonates catalysed by silicon-based main chain poly-imidazolium salts

A new method for the synthesis of main chain poly-imidazolium salts was developed from bisimidazole and silicon tetrachloride. These types of silicon-based poly-imidazolium salts are found to be among the most efficient metal-free heterogeneous catalysts (TOF = 90 h(-1)) for the fixation of CO2 with epoxides into cyclic carbonates under metal- and solvent-free conditions.