Construction of C–S bond via reductive cross-coupling

Sulfur-containing compounds have attracted considerable interest due to their varied applications in natural products, agriculture, pharmaceuticals, and organic materials. The development of rapid and efficient synthesis and transformation methods for these compounds is essential. The reductive coupling of electrophiles has emerged as a potent strategy for constructing sulfur-based molecules. While significant advancements have been achieved in cross-coupling reactions involving organic pseudohalides and halides, there is an increasing focus on reactions with more accessible, cost-effective, stable, yet less reactive electrophiles. This review majorly emphasizes the integration of cheap metals including nickel, cobalt iron and copper, electrochemical or photochemical reactions, and catalyst-free reductive cross-coupling techniques for the preparation of thioethers, disulfides, sulfones, and thioesters. It also examines the mechanistic insights underlying these strategies, thereby enhancing our comprehension of their potential for a broad spectrum of synthetic applications.