Biphasic selective epoxidation of styrene by t-butyl hydroperoxide to styrene oxide using potassium chromate or dichromate catalyst in aqueous medium

Styrene oxide with high selectivity (>60%) at high conversion (>50%) can be produced in the biphasic epoxidation of styrene by t-butyl hydroperoxide, using easily separable potassium chromate or dichromate as catalyst in the presence of water; the reactants and products exist in the non-aqueous (organic) phase, while the catalyst exists in the aqueous phase. Both potassium chromate and dichromate catalysts show very high activity in the biphasic epoxidation; however, a more preferable catalyst is potassium chromate. (C) 2004 Published by Elsevier B.V.