Development of Photoredox‐Assisted Direct α‐Alkylation Reactions of Ketones with Arylalkenes Using a Catalytic Amount of LiOtBu as a Brønsted Base

Abstract

AbstractPhotoinduced direct α‐alkylation reactions of ketones with arylalkenes using an organophotocatalyst and a Brønsted base were developed. It was found that the choice of both Brønsted base and photocatalyst was crucial, and in the presence of catalytic amounts of 2,4,6‐tris(diphenylamino)‐3,5‐difluorobenzonitrile (3DPA2FBN) and LiOtBu, the desired reactions of ketones with styrene analogues proceeded smoothly under blue‐LED light irradiation to afford the products in moderate to high yields. This method constitutes an atom‐economical alkylation process for α‐functionalization of both cyclic and acyclic ketones.