9532. p-Toluenesulfinic Acid

Nomenclature

CAS number: 536-57-2
C7H8O2S; mol wt 156.20.
C 53.83%, H 5.16%, O 20.49%, S 20.53%.

Description and references

Prepd by reduction of p-toluenesulfonyl chloride with zinc dust: Whitmore, Hamilton, Org. Synth. 2, 89 (1922). Because the sulfinic acid is difficult to dry without partial conversion to the sulfonic acid, the sodium salt, CH3C6H4SO2Na.2H2O, is usually prepd. The free sulfinic acid is then obtained as needed by dissolving the sodium salt in cold water and carefully acidifying the soln with the exact amt of HCl needed.

Chemical structure

Properties

Long, rhombic plates or needles from water. mp 85°. Freely sol in alc, ether; sparingly sol in water, hot benzene.