7242. Phenoldisulfonic Acid

Nomenclature

CAS number: 96-77-5
4-Hydroxy-1,3-benzenedisulfonic acid; 4-hydroxy-m-benzenedisulfonic acid; 1-phenol-2,4-disulfonic acid.
C6H6O7S2; mol wt 254.24.
C 28.34%, H 2.38%, O 44.05%, S 25.22%.

Description and references

Conveniently prepd by hydrolysis of the dichloride which is obtained by the action of chlorosulfonic acid on phenol at room temp: Pollak et al., Monatsh. Chem. 46, 395 (1925). Monograph: E. E. Gilbert, Sulfonation and Related Reactions (Interscience, New York, 1965) 529 pp.

Chemical structure

Properties

Deliquescent needles, vague melting range from 89° to 100°. Decomp above 100°. Corrosive. Freely sol in water, methanol. Practically insol in ether, petr ether.

Use

In the manuf of aminophenoldisulfonic acids which are intermediates in the dye industry.