Synthesis of some 2-amino-4-phenyl-3H-1,5-benzodiazepines by reaction of aromatic diamines and acetylenic imidates

The reaction of several aromatic 1,2-diamines with conjugated acetylenic imidate salts is described. The use of hexamethylphosphoric triamide (HMPA) as the solvent allows preparation of 2-amino-4-phenyl-3H-1,5-benzodiazepines in a one-step reaction.