Oxidation of Alkenes with Aqueous Potassium Peroxymonosulfate and No Organic Solvent

Aqueous potassium peroxymonosulfate oxidizes water-immiscible alkenes at room temperature in the absence of organic solvent. Acidic (pH I 1.7) solutions of 2KHS05-KHS04.K2S04 in water produced the epoxide from cyclooctene and diols from all other reactive alkenes investigated. Adjustment of initial pH to 1 6.7 with NaHC03 enabled selective epoxidations of 2,3-dimethyl-2-butene, 1-methylcyclohexene, cyclohexene, styrene, and 8methylstyrene. The order of decreasing reactivity of alkenes was: 2,3-dimethyl-2-butene > 1-methylcyclohexene 2 cyclohexene > cyclooctene,> a-methylstyrene 1 @-methylstyrene > styrene > p-methylstyrene > allylbenzene. 1-Octene and tetrachloroethylene did not react. Phaset rader catalysts, a colloidal cationic polymer, and a cationic surfactant microemulsion had little effect on the reaction.