3,4-Toluenedithiol

3,4-Toluenedithiol is an organosulfur compound with the formula CH3C6H3(SH)2. It is encountered as a colorless wax or oil. The compound is classified as an aromatic dithiol. It forms brightly colored derivatives with many metal ions. The compound is closely related to 1,2-benzenedithiol but is often more widely used because it is less expensive. 3,4-Toluenedithiol is prepared by reduction of the bis(sulfonyl chloride) CH3C6H3(SO2Cl)2 with tin.

It has been investigated as a probe of thiol-disulfide reactions.

"Dithiol"
Under the name "dithiol", 3,4-toluenedithiol was popularized as a reagent in qualitative inorganic analysis. It was promoted as an alternative to hydrogen sulfide since it also forms colorful solid precipitates with a variety of metal ions.