Cyclodehydration of 5-((carboxymethyl)amino)pyrimidines: synthesis and characterization of novel mesoionic imidazo(1,2-c)pyrimidin-3-ones

Imidazo(1,2-c)pyrimidin-3-one compounds are produced by the cyclodehydration of 5-(carboxymethy)amino-substituted pyrimidines using acid anhydrides. X-ray crystal structure studies reveal the bicyclic type A(super-1) mesoionic-like structures of the compounds. These compounds possess a combination structure of a valence tautomer and a resonance hybrid and are mesoionic. Substituted alkyl halides, under basic reaction conditions, alkylate the position N-1, where the compound has no blocking group.