Development of highly active SO3H-modified hybrid mesoporous catalyst

Ethenylene groups on the framework of hybrid mesoporous ethenylene-silica (HME) were successfully modified by a two-step chemical modification (Diels-Alder reaction, sulfonation) to obtain hybrid mesoporous solid acid catalyst. The pendant phenylene groups were first introduced at the ethenylene sites on the surface by the Diels-Alder reaction with benzocyclobutene. The introduced phenylene groups were then sulfonated by simple treatment with concentrated H2SO4. The successful formation of phenylene-sulfonic acid groups at the ethylene sites was confirmed by C-13 and Si-29 nuclear magnetic resonance (NMR) analysis. X-ray diffraction (XRD) measurements and N-2 adsorption analysis revealed the preservation of the original mesoscopic ordering and mesoporosity after the modification. The resulting material exhibited high activity for various acid-catalyzed reactions and can be used repeatedly without deactivation. (C) 2006 Elsevier B.V. All rights reserved.