Gif chemistry: new evidence for a non-radical process

When performed under a nitrogen monoxide atmosphere, Gif oxidation of cyclohexane with hydrogen peroxide gives no changes in activity or selectivity, showing that triplet oxygen is neither formed nor required in the oxidation. Gif oxidation of cis- and trans-decalin occurs preferentially at secondary positions giving high yields of ketones. Oxidation of tertiary positions is as low as approximately 5% and probably involves free radicals. Oxidation of cyclohexane in the presence of mannitol gives no significant loss of activity, showing that OH radicals are not involved in Gif oxidation. Based on these results the mechanism of Gif oxidation is discussed.