Highly Enantioselective Cu-Catalyzed Synthesis of Propargylamines

Significance

The biological relevance of propargylamines and their great synthetic utility make their enantioselective synthesis an interesting challenge. Access to propargylamines via metal-catalyzed addition of alkynes on enamines has first been reported by Knochel et al. (Angew. Chem. Int. Chem. 2002, 41, 2535-2538). However, in order to extend the reaction to aldehydes from which enamines cannot be prepared, a three-component reaction between an alkyne, an aldehyde and a secondary amine had to be developed. A broad range of substrates is tolerated in this reaction to give the expected product in good to excellent ee.