Recent Advances in Transition-Metal Catalyzed Cross Coupling Reactions of Sulfonium Salts for the Synthesis of C-C and C-X Bonds

Sulfonium salts have emerged as versatile precursors in constructing C-C and CX bonds with enhanced selectivity and functional group tolerance. This review mainly summarizes advancements from 2019 to 2025 in transition-metal-catalyzed cross-coupling methodologies utilizing sulfonium salts, emphasizing their unique advantages over traditional alkyl halides. Key methodologies, including photoredox catalysis, nickel- and palladium- catalyzed transformations, are discussed. Innovations in synthesizing complex molecules, such as 2-benzylpyrrolidines, and arylindoles, are featured. This review also discusses various reaction mechanisms and strategies for site-selective functionalization. We hope this review will promote the development of sulfonium salts.