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

Heterogeneous molybdenum-containing polymeric catalysts for the epoxidation of alkenes by organic hydroperoxides were prepared by a simple treatment o f the chelating ion exchange resins (polyampholites) Amberlite IRC718, Ambe rlite IRC748 and Duolite C467 (Rohm&Haas, USA) with both the aqueous soluti on of sodium molybdate at pH 3.5 and solution of molydenyl acetylacetonate in toluene. The formation of the catalytically active centres by the intera ction of the oxomolybdenum species from the reaction solution with ligand f unctional groups of the ion exchangers was proved. The stability of these p olymeric complexes on multiple use with the epoxidation of cyclohexene by t ert-butylhydroperoxide (TBHP) in the absence of an inert solvent at tempera ture 79 degrees C and initial TBI-IP concentration of 1.2-1.3 mol l(-1) was studied. (C) 2000 Elsevier Science B.V. All rights reserved.