o-sulfobenzoic Acid

Name:
o-sulfobenzoic Acid
Detailed information:

M Formula:	HO3SC6H4COOH
Properties:
White needles. Mp 68–69C (with 3H2O of crystallization), mp 134C (dry). Soluble in water and alcohol; insoluble in ether.
Derivation:
(1) From saccharin and concentrated hydrochloric acid, (2) by the oxidation of thiosalicylic acid with potassium permanganate in alkaline solution.
Use:
Manufacture of sulfonaphthalein indicators, dyes.