Decarboxylative Thiolation of Redox-Active Esters to Thioesters by Merging Photoredox and Copper Catalysis.

Thioesters and related thiols are critically important to biological systems and also widely employed in the synthesis of pharmaceutically important molecules and polymeric materials. However, known synthetic methods often suffer from the disadvantage of being specific only to certain substrates. Herein, we describe a facile decarboxylative thioesterification of alkyl acid derived redox-active esters by merging photoredox catalysis and copper catalysis. This reaction is applicable to a wide range of carboxylic acids, as well as natural products and drugs, allowing for the synthesis of various thioesters with diverse structures, including tertiary ones that are not accessible via traditional nucleophilic substitution from tertiary halides. Moreover, product utilization is demonstrated with a direct transformation of thioesters to sulfonyl fluorides.