Grafted ionic liquid: Catalyst for solventless cycloaddition of carbon dioxide and propylene oxide

An ionic liquid 1-(triethoxysilyl)propyl-3-methylimidazolium hydroxide ([Smim]OH) was grafted on silica gel with different amount by post-grafting method. Such grafted ionic liquids (GILs), which were verified by means of FTIR, element analysis, 29Si MAS NMR and N2 adsorption–desorption could be used as highly effective heterogeneous catalysts toward propylene carbonate synthesis through cycloaddition of CO2 with propylene oxide under solventless and mild conditions.