New selective oxidation reactions by nitroarenes in basic medium involving electron-transfer processes

A new synthetic process for oxidation of methyl ketones into their corresponding carboxylic acids using a modified alkaline nitrobenzene method is described. By introduction of a more powerful oxidant, such as 1,3-dinitrobenzene, the oxidation reaction proceeds smoothly in aqueous alkaline solution at 100 degreesC, The procedure can also be used for oxidation of benzaldehydes and benzyl alcohols into carboxylic acids and to oxidise mandelic acid into its alpha -keto form, whereas prolonged reaction time results in decarboxylation and gives thus also in this case benzoic acid.