Oxidative N−N Bond Formation Versus the Curtius Rearrangement

Abstract

The oxidative formation of N–N bonds from primary amides has been recently reported and then retracted in the journal Nature Communications by Kathiravan, Nicholls, and coauthors, utilizing a hypervalent iodane reagent. Unfortunately, the authors failed to recognize the Curtius reaction taking place under the described reaction conditions. Thus, the claimed N–N coupling products were not formed. Instead, the Curtius rearrangement urea coupling products were obtained. We demonstrate this herein by means of NMR and x‐ray analysis, as well as with the support of an alternative synthetic route.