Radical C–C bond formation using sulfonium salts and light

Sulfonium salts are playing an increasingly significant role in contemporary organic synthesis. In particular, the generation of radicals from sulfonium salts is a fundamental process in Nature and has been the subject of investigation for over 50 years. However, general synthetic methods that use sulfonium salts as radical precursors are rare. The advent of photoredox catalysis has triggered an upsurge of interest in the radical chemistry of sulfonium salts and this review surveys recent applications of aryl and alkyl sulfonium salts in light‐mediated, radical C–C bond formation.