Oxidative Recyclization of 1<i>H</i>-Indoles for Synthesis of 2-Indolylbenzoxazinones via Cleavage of the C2–C3 Bond with AIBN under Air

A novel and concise method for the oxidation of unprotected indole derivatives to synthesize 2-indolylbenzoxazinones in the presence of AIBN under open air has been successfully demonstrated. This metal-free reaction is both atom- and step-efficient and is applicable to a broad scope of substrates. This new methodology provides a facile pathway for oxidative C2-C3 bond cleavage and recyclization of 1H-indoles.