Propargylamines are synthesized from methyl vinyl ketone derivatives, 1-alkynes, and secondary amines
catalyzed by Cu salts involving the Michael addition of amine followed
by an unusual C–C bond cleavage and addition of metal acetylides
formed in situ to iminium ions. In this approach, the di-, tri-, and
tetrasubstituted propargylamines are synthesized in 46–98%
yields.