A novel method for the synthesis of pyrimido[1,2-a]benzimidazoles

[Figure not available: see fulltext.] Condensation of 1,2-diaminobenzimidazole with N-arylitaconimides was studied. It was found that 2-(10-amino-N-aryl-2-oxo-2,3,4,10-tetrahydropyrimido[1,2-a]benzimidazol-3-yl)acetamides were formed in the course of this reaction upon brief heating to reflux of the reagent mixture in 2-propanol in the presence of catalytic amounts of acetic acid. © 2016, Springer Science+Business Media New York.