Enantioselective Gold(I)-Catalyzed Hydrative Cyclizations of N-Propargyl-ynamides into 3,6-Dihydropyridinones.

This study discloses the first enantioselective variant of the gold(I)-catalyzed hydrative cyclizations of ynamides, which have been implemented by using bis-gold(I) complexes of chiral diphosphines. Starting from N-propargyl-ynamides and water in the presence of p-toluenesulfonic acid, the cyclization reactions afford N-tosyl-3,6-dihydropyridin-2(1H)-ones in good isolated yields and with high levels of stereocontrol (20 examples, enantiomeric ratios up to 94:6).