As 3-aza-1,5-enynes, internal and terminal alkyne-bearing tertiary enamides underwent an efficient Au(I)-catalyzed 6-endo-dig cyclization reaction to afford a variety of di- to penta-substituted 1,2-dihydropyridine derivatives in high yields. The cyclization proceeds through a cascade comprising an intramolecular nucleophilic addition of enaminic carbon to alkyne–gold(I) complex, deprotonation, and protodeauration steps. Au(I)-catalyzed tertiary enamide–alkyne cyclization coupled with consecutive oxidative aromatization provided a straightforward route to polysubstituted pyridines.
Alkynes are found in a multitude of natural or synthetic bioactive compounds. In addition to the capacity of these chemical motifs to impact the physicochemical properties of a molecule of interest, the well-established reactivity of alkynes makes them ...