Cobalt-Catalyzed Hypervalent Iodine(III) Promoted Cascade Annulation Reaction of Anilines with Formamides for 2-Aminobenzoxazoles Synthesis.

Herein, we disclose a practical and simple procedure to synthesize 2-aminobenzoxaoles. Simple anilines and formamides were used as substrates. The C-H bond ortho to the amino group in the anilines was directly functionalized under cobalt-catalyzed conditions with high levels of functional group tolerance. Hypervalent iodine(III) was both an oxidant and a Lewis acid for this reaction. The mechanism study showed that this transformation may involve a radical process.