Naphthionic Acid

Name:
Naphthionic Acid
Detailed information:

Chemistry name:	1-naphthylamine-4-sulfonic acid; 1-aminonaphthalene-4-sulfonic acid; 4-amino-1-naphthalenesulfonic acid
Chemistry structure:
Properties:
White crystals or powder. Soluble in water; slightly soluble in alcohol and ether.
Derivation:
Heating equimolar amounts of α-naphthylamine and sulfuric acid at 10–15 mm Hg (several hours).
Use:
Intermediate for azo dyes, e.g., Congo red.