Basic alumina supported solvent-free one-pot synthesis of pyridine-fused polycyclic diazepaniums was achieved under microwave irradiation. The process was successfully extended to the synthesis of pyridine-fused bicyclic imidazolidiniums and tetrahydro- pyrimidiniums and also of tri-and tetracyclic diaza-heterocycle-fused quinoliniums. The dual characteristic of basic alumina, a solid support as well as a base, was successfully ...