Metal‐Free Oxidative Amidation of 2‐Oxoaldehydes: A Facile Access to α‐Ketoamides.

A novel and efficient method for the synthesis of α-ketoamides, employing a dimethyl sulfoxide (DMSO)-promoted oxidative amidation reaction between 2-oxoaldehydes and amines under metal-free conditions is presented. Furthermore, mechanistic studies supported an iminium ion-based intermediate as a central feature of reaction wherein C1-oxygen atom of α-ketoamides is finally derived from DMSO.