Heterogeneous enantioselective epoxidation catalyzed by Mn(salen) complexes grafted onto mesoporous materials by phenoxy group

Three chiral Mn(salen) complexes immobilized into various mesoporous materials via phenoxy group by a simplified method show remarkably higher ee values for asymmetric epoxidation of α-methylstyrene (79.7 versus 26.4%) and cis-β-methylstyrene (94.9 versus 25.3%) than the homogeneous catalysts. The heterogeneous catalysts also obviously alter the cis/trans ratio of epoxide (homogeneous 0.38 versus heterogeneous 21).