Photo-Induced Intermolecular N–N Cross-Coupling via Nitrene Transfer Reaction

An intermolecular N-N cross-coupling reaction induced by light was established under metal-free conditions. In addition, this work showed that pyrido-oxazolones serve as effective nitrene precursors under photoinduced conditions, facilitating cross-coupling reactions to synthesize a diverse array of hydrazides at room temperature. The developed cross-coupling is operationally simple and provides a streamlined synthetic protocol for the late-stage functionalization of bioactive molecules. Mechanistic studies and theoretical calculations suggested that the reaction proceeds through the formation of a free nitrene, which further interacts with the <i>N</i>-alkyl or <i>N</i>-aryl anilines to produce the hydrazine products with a pyridyl unit. This photoactivated N-N cross-coupling reaction is anticipated to find extensive applications in medicinal chemistry, drug development, and the pharmaceutical industry.