A Highly Chemoselective Synthesis of Cyclic Divalent Propargylamines by Copper‐Catalyzed Annulation/Double A3‐Couplings

Divalent propargylamines are prominent intermediates in the preparation of multidentate ligands, which have wide implications for use in catalysis. Herein, a highly chemoselective and versatile protocol for the construction of cyclic divalent propargylamines has been achieved under microwave irradiation. This sequential transformation comprises a copper‐catalyzed annulation/A3‐coupling/A3‐coupling of a primary diamine with formaldehyde solution and two alkynes to directly providing a diverse set of N,N′‐dipropargylimidazolidines and hexahydropyrimidines in moderate to excellent yields.