One-step multicomponent synthesis of 4-amino-2-aryl-3-cyano-1,2-dihydropyrimido[1,2-a]benzimidazoles

Abstract

This paper describes the synthesis of a new serie of 4-amino-2-aryl-3-cyano-1,2-dihydropyrimido[1,2-a]benzimidazoles 4a-f from the reaction of 2-aminobenzimidazole 1 with malonodinitrile 2 and benzaldehydes 3. The structure elucidation of the products is based on detail nmr analysis of experiments such as 1H-COSY, NOESY, DEPT, HSQC and HMBC.