Chemoselective chloroperoxidase-catalyzed oxidation of hexen-1-ols

The chemoselectivity of chloroperoxidase from Caldariomyces fumago has been studied for the oxidation of cis- and trans-hexen-1-ols with tert-butyl hydroperoxide in a two-phase system of hexane or cyclohexane and citrate buffer (4: 1, v/v; pH 5.0). In the hexen-1-ols used, the position of the C = C bond varied systematically from position 2 to position 5. According to GC analysis, the main oxidation product was always the corresponding aldehyde, and the epoxidation product was seen only in the case of 4-hexen-1-ols. For trans-4-hexen-1-ol, the amount of detectable oxidation products generally stayed extremely low although the alcohol itself disappeared smoothly with time, suggesting extensive condensation/ring opening as further reactions of the produced aldehyde and epoxyalcohol.