Photochemical reductive coupling of α-keto esters for synthesizing 2,3-diarylated tartaric acid esters

Abstract

A metal- and photocatalyst-free method for reductive homocoupling of α-ketoesters using ascorbic acid as a mild hydrogen source is reported. This approach avoids stoichiometric amounts of strong reductants or complex photocatalysts. The method tolerates various functional groups, enables synthesis of quaternary carbon centers, and is scalable to the gram level.