Efficient and convenient synthesis of ionic liquid supported SBA-15 mesoporous srganosilica and its beneficial applications in henry reaction

Compared with post-grafting method, a novel and controllable strategy is applied to introduce highly dispersed ionic liquid species into mesoporous SBA-15 silica, providing simpler synthesis steps, more uniform surface coverage and higher loading of ionic liquid, with fewer raw materials. Basic task-specific ionic liquids are synthesized and characterized by X-ray diffraction, N₂ adsorption-desorption, thermogravimetry and fourier transform infrared spectroscopy. The results showed that the catalysts, prepared by co-condensation method, have better ordered mesostructure and higher loading of ionic liquid than those by post-grafting approach. Meanwhile, the catalysts exhibit much higher activity than those by post-grafting approach in Knoevenagel condensation. Furthermore, these supported catalysts are also proven to be efficient and reusable in Henry reaction under solvent-free conditions.