Titanium Incorporated Mesoporous Silica Immobilized Functional Ionic Liquid as an Efficient Reusable Catalyst for Cycloaddition of Carbon Dioxide to Epoxides

A series of functionalized ionic liquids immobilized onto SBA-15 mesoporous materials were prepared, characterized and evaluated as catalysts in cycloaddition of CO, to epoxides. Most of these immobilized ILs perform well in the reaction, especially the multifunctional titanium incorporated SBA-15 immobilized heterogeneous catalysts Ti-SBA-15@ILClCH2COO(0.5) and Al-SBA-15@ILClCH2COO(0.5). The catalytic tests revealed that Ti-SBA-15@ILCICH2COO(0.5) was the best and powerful catalyst in the cycloaddition for the preparation of cyclic carbonates with high to excellent yields. The heterogeneous catalyst can be easily separated from the reaction mixture by filtration and reused in six consecutive cycles without significant loss in catalytic activity. The studies demonstrate that the well designed supported catalysts via cooperative catalysis of the supported carrier, anion sites of ILs is a promising platform for construction of novel and highly efficient catalytic transformation systems.