Selective epoxidation of alkenes with hydrogen peroxide over efficient and recyclable manganese oxides

A series of manganese oxides (MnO, Mn(3)O(4), Mn(2)O(3) and MnO(2)) were prepared and firstly applied as heterogeneous catalysts for the liquid phase epoxidation of alkenes with 30% H(2)O(2) in bicarbonate solution. Under our experimental conditions. MnO exhibited superior activity for the conversion of styrene to achieve ca. 100% with 92.4% selectivity of epoxide, compared to the other three manganese oxides as well as other metal oxides. Furthermore, recycling studies showed the good recyclability of MnO as a heterogeneous catalyst, which did not lose the catalytic activity after four reuses appreciably. (C) 2011 Published by Elsevier B.V.