Organocatalytic asymmetric formal arylation of benzofuran-2(3H)-ones with cooperative visible light photocatalysis.

An organocatalytic asymmetric reaction of benzofuran-2(3H)-ones with naphthoquinones is disclosed. The current method provides a direct way to facilitate arylation of benzofuran-2(3H)-ones in high yields with excellent enantioselectivities. A cooperative visible light photocatalysis with asymmetric hydrogen-bond catalysis has also been developed, thus allowing the more widely available 1-naphthols instead of naphthoquinones to be applied to facilitate the arylation with satisfactory results (up to 95% ee).