CuCl2-Catalyzed one pot synthesis of imidazohetrocycles and furo[3,2-c]chromenyl fused imidazoles

Abstract

A new route to diverse set of imidazoheterocycles is developed via anhydrous CuCl2 catalyzed aza-annulation reaction of several oxime esters with 2-amino-azaarenes. Gratifyingly, implementation of this chemistry is further stretched for the synthesis of furo[3,2-c]chromenyl fused imidazoles via squential C-N bond formation, follwed by 5-endo-dig-oxacyclization of in situ produced fused imidazoles with cyclic enynones in the presence of CuCl2 as the naturally available lewis acid catalyst.