Catalytic epoxidation of alkenes in the presence of a weakly acidic cation exchanger containing transition metal ions

Heterogeneous polymeric catalysts containing Mo, V and Ti for the epoxidation of alkenes by organic hydroperoxides were prepared by a simple modification of the weakly acidic cation exchanger Wofatit CA 20 (Germany) with aqueous solutions of the corresponding inorganic salts. The molybdenum-containing catalyst showed the highest activity for the epoxidation of cyclohexene in benzene solution of t-butylhydroperoxide (TBHP, 0.490-1.200 mol l(-1)) at 79 degrees C. The catalytic activity for alkenes with different structures was evaluated and compared to other catalysts under the similar conditions of cyclohexene epoxidation. Some data concerning the catalyst stability on heating and multiple recycling were also obtained. (C) 1999 Elsevier Science B.V. All rights reserved.