A gold-catalyzed cyclization/nucleophilic addition reaction of o-alkynylanilines with ynamides: stereoselective synthesis of 3-vinylindoles

Functionalized 3-vinylindoles were obtained through the cyclization/nucleophilic addition of ynamides and o-alkynylanilines catalyzed by a gold catalyst with high stereoselectivity and site-selectivity. The theoretical research suggested that the C-alpha of ynamides activated by the gold complex was favorable for the addition at the C3 position of indoles. Additionally, JohnPhosAu(MeCN)SbF6 could efficiently reduce the activation energy barrier of the addition process compared to PicAuCl(2) and Au(PPh3)NTf2, and the steric hindrance effect of JohnPhosAu(MeCN)SbF6 facilitates the formation of 3-vinylindoles with the E configuration.