Imidazo[1,2-a]benzimidazole derivatives

Research paper by A. M. Simonov, V. A. Anisimova

Indexed on: 01 May '71Published on: 01 May '71Published in: Chemistry of Heterocyclic Compounds


3-Amino derivatives of 9-alkyl(benzyl)-2-arylimidazo[1,2-a]benzimidazoles, obtained by the reduction of the appropriate 3-nitro(nitroso) derivatives, are extremely unstable, and the imidazole ring opens readily resulting in conversion to 2-(α-carboxybenzylamino)benzimidazoles. The reaction apparently proceeds through the intermediate formation of 2-(β-cyanobenzylamino)benzimidazole, which is a tautomeric form of the 3-amino compound and can react as such to form 3-acylamino derivatives and anils. If there is a methyl group in the 3-position of the ring, the amine is quite stable and can be isolated in free form.