1,3-Propanedithiol is the chemical compound with the formula HSCH<sub>2</sub>CH<sub>2</sub>CH<sub>2</sub>SH. This dithiol is a useful reagent in organic synthesis. This liquid, which is readily available commercially, has an intense stench.
1,3-Propanedithiol has been used for the protection of aldehydes and ketones via their reversible formation of dithianes. A prototypical reaction is its formation of 1,3-dithiane from formaldehyde. The reactivity of this dithiane illustrates the concept of umpolung. Alkylation gives thioethers, e.g. 1,5-dithiacyclooctane. The unpleasant odour of 1,3-propanedithiol has encouraged the development of alternative reagents that generate similar derivatives.
Oxidation gives not the 1,2-dithiolane, but the bis(disulfide).
1,3-Propanedithiol is used in the synthesis of tiapamil.
1,3-Propanedithiol reacts with metal ions to form dithiolates. Illustrative is the synthesis of the derivative diiron propanedithiolate hexacarbonyl upon reaction with triiron dodecacarbonyl:
The stench of 1,3-propanedithiol can be minimized with bleach.