Immobilized chiral Mn (III) salen-containing onium salt onto ZnPS-PVPA for asymmetric epoxidation of unfunctionalized olefins

A series of chiral Mn (III) salen are anchored on ZnPS-PVPA modified by onium salt and characterized. In the asymmetric epoxidation of unfunctionalized olefins with m-CPBA and NaIO4 as oxidants, the supported catalysts demonstrate higher catalytic activities than those of the corresponding homogeneous chiral Mn (III) salen catalyst under the same conditions both for experimental scale and for large-scale reactions. Moreover, the catalysts are stable could be recycled nine times without significant loss of activity, which are provided with the potentiality for application in industry.