One-pot CuI/l-proline-catalysed multicomponent synthesis of pyrido[2′,1′:2,3]imidazo[4,5-c]quinoline derivatives from 2-(2-bromophenyl)imidazo[1,2-a]pyridines, NH3 and DMSO under air

Abstract

In a new approach, a series of pyrido[2′,1′:2,3]imidazo[4,5-c]quinoline (PIQ) derivatives were prepared in high yields from 2-(2-bromophenyl)imidazo[1,2-a]pyridines, NH₃ and DMSO via a tandem process including CuI/L-proline-catalysed C–N coupling and aerobic oxidative cyclization steps. Consequently, this method could be applied for the synthesis of a series of thiazolo[2′,3′:2,3]imidazo[4,5-c]quinolines and benzo[4′,5′]thiazolo[2′,3′:2,3]imidazo[4,5-c]quinolines in good yields via a similar approach.