Synthesis of 2-Keto(hetero)aryl Benzox(thio)azoles through Base Promoted Cyclization of 2-Amino(thio)phenols with α,α-Dihaloketones

An interesting base-promoted protocol for the synthesis of 2-keto(hetero)aryl benzox(thi)azoles has been developed. Starting from commercially available 2-amino(thio)phenols and α,α-dihaloketones, moderate to good yields of the corresponding heterocycles can be achieved. Notably, only EtNH2 was required as the promoter here, and the reaction can be easily performed on a large scale.