A Photochemical Strategy for N-Aryl-ortho-Phenylenediamines Synthesis via Dearomative-Rearomative Coupling of Aryl Azides and Anilines

Abstract

This article describes a novel strategy for the synthesis of N-aryl-ortho-phenylenediamines from aryl azides and anilines. The process employs low-energy photoexcitation to generate singlet nitrenes via the decomposition of aryl azides. The nitrene undergoes a dearomative N-insertion that, in the presence of a Lewis acid additive, enables aniline nucleophiles to be incorporated into the 3H-azepine product. Subsequent treatment with the electrophile Boc₂O triggers a 7-to-6 ring contraction that rearomatizes the system to give N-aryl-ortho-phenylenediamines.

Keywords

Singlet nitrene - Aryl azides - Ring expansion - Azepines - Lewis acids - Ortho-phenylenediamine - N-Insertion

Publication History

Received: 13 October 2025

Accepted after revision: 28 November 2025

Accepted Manuscript online:
28 November 2025

Article published online:
24 December 2025

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