Selective β-oxidation of α-sulfanyl amides

A selective β-oxidation of a series of α-sulfanyl amides to the corresponding β-oxo-α-sulfanyl amides is described. This selective efficient oxidation of an unfunctionalised methyl or methylene group occurs under mild conditions, involving three sequential transformations conducted without isolation of the intermediates. Critically neither the sulfur nor the reactive α-CH bond is affected in the overall process.