Synthesis of perimidine and 1,5-benzodiazepine derivatives using tamed Brønsted acid, BF3–H2O

The one pot synthesis of perimidine and 1,5-benzodiazepine derivatives via condensation of aryldiamines with ketones in the presence of BF3–H2O is described. BF3–H2O plays a dual role, as an efficient non-oxidizing Brønsted acid catalyst as well as an effective solvent making the reaction more economic and environmentally safer. The reaction is simple, fast and convenient.