Oxidation of alcohols with nitroxyl radical under polymer-supported two-phase conditions

The oxidation of alcohols to carbonyl compounds was studied using potassium hexacyanoferrate(III) mediated by nitroxyl radical as the catalyst under polymer-supported organic–aqueous two-phase conditions. Primary alcohols are readily oxidized to the corresponding aldehydes in excellent yield with no over-oxidation to carboxylic acids. Secondary alcohols are converted to the corresponding ketones with a much lower efficiency. The oxidation reactions of primary alcohols in the presence of secondary alcohols is strongly favored. Primary-secondary diols are selectively transformed into hydroxy aldehydes with small amounts of ketoaldehydes, the amount of isomeric keto alcohols remaining is less than 1%.