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 less-than-or-equal-to 1.7) solutions of 2KHSO5.KHSO4.K2SO4 in Water produced the epoxide from cyclooctene and diols from all other reactive alkenes investigated. Adjustment of initial pH to greater-than-or-equal-to 6.7 with NaHCO3 enabled selective epoxidations of 2,3-dimethyl-2-butene, 1-methylcyclohexene, cyclohexene, styrene, and beta-methylstyrene. The order of decreasing reactivity of alkenes was: 2,3-dimethyl-2-butene > 1-methylcyclohexene greater-than-or-equal-to cyclohexene > cyclooctene > alpha-methylstyrene greater-than-or-equal-to beta-methylstyrene > styrene > p-methylstyrene > allylbenzene. 1-Octene and tetrachloroethylene did not react. Phase-transfer catalysts, a colloidal cationic polymer, and a cationic surfactant microemulsion had little effect on the reaction.