Heterogeneous Catalytic Epoxidation: High Limonene Oxide Yields by Surface Silylation of Ti-MCM-41

Limonene oxide is an intermediate getting growing attention in industrial chemistry. A series of Ti-MCM-41 heterogeneous catalysts with different hydrophilic/hydrophobic character, prepared by post-synthesis silylation with hexamethyldisilazane (HMDS), were studied in the liquid-phase epoxidation of limonene with tert-butylhydroperoxide (TBHP). A maximum yield of 84% in limonene oxide was obtained over a partially silylated catalyst with a surface coverage of 55 %.