Sulfur-containing heterocyclic compounds such as thiazole, thiophene, thiopyrone, widely exist in numerous natural products and biologically active molecules. Developing of effective strategies for the formation of sulfur-containing heterocycles has become a popular research hotspot. Meanwhile, the free-radical cascade reaction of unsaturated bonds in the synthesis of heterocycle has always been an important branch of synthetic chemistry, and the achieved progresses in recent years have also demonstrated its huge potential. Researchers found that sulfur atom could act as radical acceptors to build a C-S bond, and established a series of free radical reactions through this strategy. Among them, the radical cascade reactions of anisole derivatives have been gradually developed into an important synthetic tool toward sulfur-containing heterocycles. The recent advances in the field of radical-initiated reactions of anisoles for the construction of sulfur-containing heterocycles, in which sulfur atoms play as radical acceptors, are summarized. In addition, the reaction design, mechanism and applicability of sulfur-containing heterocyclic compounds via radical cyclization towards the synthesis of complex molecules are also covered.

Key words: anisole, heterocycle, radical cascade reaction, difunctionalization