A Modular Approach to Access 1,4-Benzoxazinones, Spirooxazolidinones, and 4,1-Benzoxazepinones via Oxidative Aryl C–N Bond Formation Using Catalytic Hypervalent Iodine

Herein, we present a highly efficient (one-pot) and unprecedented method for synthesizing 1,4-Benzoxazinones and 4,1-Benzoxazepinones under transition metal-free conditions through direct aryl C-H amination. For the first time, this work harnesses the 1,3-bis-electrophilic potential of α-bromohydroxamates, enabling direct O-alkylation of phenols and benzyl alcohols via an in situ-generated aza-oxyallyl cation, followed by aryl C-H amination via a nitrenium ion catalyzed by hypervalent iodine. When p-OMe-substituted phenols are used, the current system produces spiroxazolidinones, a class with limited, radical-based methods reported in the literature. Late-stage modifications of natural products and other valuable synthetic transformations underscore the synthetic utility of the method.