Oxidation of hydroxylamine derivatives. I. Anodic oxidation of hydroxamic acids.

Abstract

The anodic oxidation of hydroxamic acids in acetonitrile were studied. These hydroxamic acids generally showed two or three waves at a glassy-carbon electrode and the Ep values were larger than those of the corresponding hydroxylamines. On oxidation, O-alkylated hydroxamic acids consumed one electrone per molecule and other hydroxamic acids consumed two. Aceto-and benzohydroxamic acids gave the corresponding carboxylic acids and nitrous oxide. N-Substituted hydroxamic acids gave the corresponding nitroso compounds and carboxylic acids. O-Alkylated hydroxamic acids underwent intramolecular rearrangement of acyl and O-alkyl group to give esters, acids and alcohol. In the presence of added amines, acyl groups were recovered as amides. From these results we proposed plausible chemical processes for the anodic oxidation of hydroxamic acids.