Oxidation of substituted 1,5-hexadien-3-ols with various oxidants

Abstract

Substituted 1,5-hexadien-3-ols were synthesized by the [2,3]-Wittig rearrangement of unsymmetrical bis-allyl ethers, as well as by reactions of 1-(2-alkenyl)-2-chloromethyloxiranes with Mg/THF. The products were oxidized with pyridinium chlorochromate (PCC), zinc chlorochromate (ZCC), tert-butyl hydroperoxide in the presence of OsO4, and tent-butyl hydroperoxide alone. The oxidation of substituted 1,5-hexadien-3-ols with PCC and ZCC gave the corresponding carbonyl compounds. In the reaction with tertbutyl hydroperoxide catalyzed by OsO4 the internal double bond in the substrate was regioselectively converted into epoxy group, whereas allylic oxidation was prevented.