Unexpectedly Simple Synthesis of Benzazoles by tBuONa‐Catalyzed Direct Aerobic Oxidative Cyclocondensation of o‐Thio/Hydroxy/Aminoanilines with Alcohols under Air.

tBuONa-catalyzed direct aerobic oxidative cyclocondensation reactions of readily available alcohols and o-thio/hydroxy/aminoanilines under air have been developed and provide an efficient, practical, and green method for the synthesis of benzazoles. Mechanistic studies revealed that o-substituted anilines promote the initial aerobic alcohol-oxidation step, which explains the high reactivity and success of this unexpectedly simple and practical cyclocondensation method.