A new, one-pot, multi-component synthesis of imines of 3-amino-2-arylimidazo[1,2-a]pyridines, 3-amino-2-arylimidazo[1,2-a]pyrazines, and 3-amino-2-arylimidazo[1,2-a]pyrimidines

An efficient, one-pot, multi-component synthesis of 3-amino-2-arylmidazo[1,2-a]pyridines, 3-amino-2-arylimidazo[1,2-a]pyrazines, and 3-amino-2-arylimidazo[1,2-a]pyrimidines is described. Heating a Mixture of a 2-aminopyridine, 2-aminopyrazine or 2-aminopyrimidine, a benzaldehyde, and imidazoline-2,4,5-trione Under solvent-free conditions afforded imine derivatives of the title compounds in excellent yields. Single-crystal X-ray analysis conclusively confirms the structure of these bridgehead bicyclic 5-6 heterocycles. (C) 2008 Published by Elsevier Ltd.