Aminonaphthalenesulfonic acids are compounds with the composition , being derived from naphthalene () substituted by an amino and sulfonic acid groups. These compounds are colorless solids. They are useful precursors to dyes.Gerald Booth "Naphthalene Derivatives" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. .
+ 1-Aminonaphthalenesulfonic acids Isomer CAS Registry Number Alternative names Preparative route, notes1-Aminonaphthalene-2-sulfonic acid 81-06-1 ortho-naphthionic acid heating sodium naphthionate induces net migration of sulfonate to 2-position 1-Aminonaphthalene-4-sulfonic acid 84-86-6Piria’s acid, naphthionic acidsulfonation of 1-aminonaphthalene, precursor to acid red 25, C.I. food red 3, C.I. food red 7, C.I. food red 9, and C.I. 1-Aminonaphthalene-5-sulfonic acid84-89-9Laurent’s acid, L acid, Purpurin acidreduction of 1-nitronaphthalene-5-sulfonic acid. With NaOH, converts to 5-amino-1-naphthol ("purpurol"). 1-Aminonaphthalene-6-sulfonic acid119-79-91,6-Cleve’s acid (named after swedish chemist Per Teodor Cleve)sulfonation of 1-aminonaphthalene 1-Aminonaphthalene-7-sulfonic acid119-28-81,7-Cleve’s acidby-product in production of 1,6-Cleve’s acid, precursor to C.I. Acid Black 36 1-Aminonaphthalene-8-sulfonic acid82-75-7Peri acidreduction of 1-nitronaphthalene-8-sulfonic acid, precursor to C.I. Acid Blue 113 1-Aminonaphthalene-2-hydroxy-4-sulfonic acid 116-63-2 - from nitroso-β-naphthol
Notes: Peri-acid dehydrates to the sultam. Via the Bucherer reaction, heating periacid with anilinium salts gives the N-phenyl derivative, precursor to Acid Blue 113.
+ 2-Aminonaphthalenesulfonic acids Isomer CAS Registry Number Alternative names Preparative route and notes 2-Aminonaphthalene-1-sulfonic acid81-16-3Tobias acid Bucherer reaction of 2-hydroxynaphthalene-1-sulfonic acid with ammonium salts, precursor to C.I. Pigment Red 49 2-Aminonaphthalene-5-sulfonic acid81-05-0Dahl’s acid, Dressel acid, D acidDesulfonation of 2-aminonaphthalene-1,5-disulfonic acid 2-Aminonaphthalene-6-sulfonic acid93-00-5 Bronner acidBucherer amination of 2-hydroxynaphthalene-6-sulfonic acid 2-Aminonaphthalene-7-sulfonic acid494-44-0 Amido F acid; Delta acid; Monosulphonic F acidBucherer amination of 2-hydroxynaphthalene-7-sulfonic acid 2-Aminonaphthalene-8-sulfonic acid 86-60-2Badische acidBucherer amination of 2-hydroxynaphthalene-8-sulfonic acid
Structure These compounds feature amines and sulfonic acid groups. According to X-ray crystallography, some members of this series, however exist as zwitterions, i.e. .
Related compounds Hydroxynaphthalenesulfonic acid
References