Some molybdenum-containing chelating ion-exchange resins (polyampholites) as catalysts for the epoxidation of alkenes by organic hydroperoxides

Abstract

Heterogeneous molybdenum-containing polymeric catalysts for the epoxidation of alkenes by organic hydroperoxides were prepared by a simple treatment of the chelating ion exchange resins (polyampholites) Amberlite IRC718, Amberlite IRC748 and Duolite C467 (Rohm and Haas, USA) with both the aqueous solution of sodium molybdate at pH 3.5 and solution of molydenyl acetylacetonate in toluene. The formation of the catalytically active centres by the interaction of the oxomolybdenum species from the reaction solution with ligand functional groups of the ion exchangers was proved. The stability of these polymeric complexes on multiple use with the epoxidation of cyclohexene by tert-butylhydroperoxide (TBHP) in the absence of an inert solvent at temperature 79°C and initial TBHP concentration of 1.2-1.3 mol 1-1 was studied. (C) 2000 Elsevier Science B.V.