A series of pyrimido[1,2‐a]benzimidazoles were obtained from aldehydes, 2‐aminobenzimidazole and ethyl acetoacetate in good‐to‐excellent yields by a simple, mild, and efficient procedure utilizing N,N,N′,N′‐tetrabromobenzene‐1,3‐disulfonamide (TBBDA) and poly(N‐bromo‐N‐ethylbenzene‐1,3‐disulfonamide) (PBBS) as catalysts.
通过使用N,N,N',N'-的简单,温和且有效的方法,从醛,2-氨基苯并咪唑和乙酰乙酸乙酯中获得了一系列嘧啶[1,2- a ]苯并咪唑,收率良好至优异。四溴苯-1,3-二磺酰胺(TBBDA)和聚(N-溴-N-乙基苯-1,3-二磺酰胺)(PBBS)作为催化剂。