| Abstract
| - The basic layered hydrotalcites have been used as catalysts for the epoxidation of α,β-unsaturatedketones in heterogeneous reaction media using hydrogen peroxide as an oxidant. A wide variety ofα,β-unsaturated ketones were oxidized to the corresponding epoxyketones in excellent yields undermild reaction conditions. For example, 2-cyclohexen-1-one gave 2,3-epoxycyclohexanone in 91% yieldat 40 °C for 5 h with high efficiency in hydrogen peroxide. The catalytic activity of the hydrotalcitesincreased as the basicity of their surfaces increased. In the case of the epoxidation of less reactivesubstrates, adding a cationic surfactant such as n-dodecyltrimethylammonium bromide (DTMAB)to the above oxidation system accelerated the epoxidation reaction. These hydrotalcite catalystswere easily separated from the reaction mixture and were reusable.
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