Microwave-assisted and Solvent-free Synthesis of Propargylamines via A3-coupling Reaction

An efficient and green method for the A³-coupling reaction of saliciladehyde, secondary amines, and terminal alkynes to synthesize propargylamines using a microwave reactor has been demonstrated. The synthesis showed several salient features, such as high yield of products, rapid product formation, and environmentally benign reaction conditions. Furthermore, the synthesis could be performed in gram scale. Nine propargylamine adducts were obtained in high yields and their structures were confirmed by NMR data. A plausible reaction mechanism was also suggested.