Chiral Salen Mn(III) complex axial coordination immobilized on diamine modified ZSPP and their catalytic epoxidation of styrene

Chiral Salen Mn(III) complex axial coordination immobilized on diamine modified zirconium oligo-styrenyl phosphonate hydrogen phosphate (ZSPP) were prepared by a covalent grafting method. All the supported heterogeneous chiral Salen Mn(III) complexes prepared were characterized by FT-IR, diffusion reflection UV–vis, AAS, N2 volumetric adsorption, SEM, TEM and TG. These supported chiral catalysts showed a little lower chiral induction (ee, 72%) contrast of its homogeneous counterpart 1 (ee, 86%) for asymmetric epoxidation of styrene in presence of NMO as axial ligands with m-CPBA as an oxidant. The catalysts were easily recovered by filtration and could be reused at least five times with little loss of activity and enantioselectivity.