α-Alkylation of Ketones with Alkenes Enabled by Photoinduced Activation of Silyl Enol Ethers in the Presence of a Small Amount of Water.

Under blue-light irradiation conditions with a photocatalyst [1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene], silyl enol ethers reacted with alkenes in the presence of a small amount of water to afford the α-alkylation products in good to high yields. A thiol cocatalyst was found to expand the substrate scope of the reaction.