Heterogeneous epoxidation of alkenes with H2O2 catalyzed by a recyclable organic-inorganic polyoxometalate-based framework catalyst

Four organic-inorganic polyoxometalate-based frameworks (HSiW-MOF, PMo-MOF, HPMo-MOF and PW-MOF) were synthesised and characterized by elemental analysis, UV-vis and FT-IR spectroscopy, cyclic voltammetry and XRD analysis. Organic-inorganic polyoxometalate-based frameworks could act as effective and reusable heterogeneous catalysts for selective epoxidation of alkenes with aqueous hydrogen peroxide in acetonitrile. In the presence of PW-MOF, various kinds of alkenes could selectively be converted into the corresponding epoxides with high conversion and selectivity. PW-MOF was stable to leaching, behaved as true heterogeneous catalysts, easily recovered by filtration, and reused four times with maintenance of the catalytic performance.