Synthesis of Benzimidazolones, Benzooxazolones, 2-amino-benzothiazoles from Ethyl Cyanoformate and o-phenylene Diamines, o-aminophenols, oaminothiophenols Promoted by Lithium Bromide

The lithium bromide mediated condensation of 1-amino-2-heteroaryl substrates with ethyl cyanoformate, to obtain versatile alkylcarbamate protected benzoheteroazolones was studied. This unprecedented reaction could be used to furnish different azolones like 2-benzimidazolones, 2-benooxazolones and 2-amino-thiazoles in good yields.