Elemental Sulfur: An Excellent Sulfur-Source for Synthesis of Sulfur-Containing Heterocyclics

Sulfur-containing heterocyclic compounds are widely applied in many areas such as drugs, molecular devices and materials, etc., so their synthesis methods have attracted much attention. The key step for the synthesis of sulfur-containing heterocycles is the construction of C-S bond, which is generally realized by C-H bond functionalization or C-X bond coupling reaction with sulfur-containing organic or inorganic substances. Elemental sulfur is cheap, available and stable, and it is an excellent sulfur atom donor for the synthesis of sulfur-containing heterocycles. Therefore, the synthesis of sulfur-containing heterocycles from elemental sulfur has become a research hotspot. Herein, the recent research progress of synthesis of sulfur-containing heterocyclic employing sulfur as sulfur-source is reviewed.