BIPHASE AND TRIPHASE CATALYSIS - ARSONATED POLYSTYRENES AS CATALYSTS FOR EPOXIDATION OF OLEFINS BY AQUEOUS HYDROGEN-PEROXIDE

Arsonated polystyrene resins have been found to be versatile catalysts for olefin epoxidation by aqueous hydrogen peroxide. In a biphase system consisting of an organic solvent miscible with aqueous hydrogen peroxide and the insoluble resin, the catalysts are efficient for epoxidation of alkenes with internal double bonds and for regio-and stereoselective epoxidation of allylic alcohols. In order to prevent epoxide hydrolysis, 90% aqueous hydrogen peroxide and an excess of olefin are recommended. Olefins can also be epoxidized in a triphase system consisting of a water immiscible solvent, aqueous hydrogen peroxide, and the solid catalyst. The advantage of the triphase system is in the efficient utilization of hydrogen peroxide and prevention of epoxide hydrolysis even if 30% aqueous hydrogen peroxide is employed. In both systems, the catalyst can be quantitatively separated by simple filtration and recycled. © 1979, American Chemical Society. All rights reserved.