A Facile and Practical Solvent-Free One-Pot Synthesis of (Z)-4-Methylene-3-selenaquinoline Derivatives from o-Ethynylanilines and Isoselenocyanates

Heating of o-ethynylanilines with isoselenocyanates directly resulted in the 6-exo-dig mode ring-closure reaction of the adducts to give the (Z)-2-imino-4-methylene-3-selenaquinolines in moderate to good yields. Based on this convenient, solvent-free, catalyst-free method, several 3-selenaquinoline derivatives (3,1-benzoselenazines) were easily obtained in one pot. Successful application of the microwave-assisted synthesis of these compounds was also investigated.