Aminonaphthalenesulfonic acids
Aminonaphthalenesulfonic acids are compounds with the composition C10H6(NH2)(SO3H), being derived from naphthalene (C10H8) substituted by an amino and sulfonic acid groups. These compounds are colorless solids. They are useful precursors to dyes.[1]
| Isomer | CAS Registry Number | Alternative names | Preparative route, notes |
|---|---|---|---|
| 1-Aminonaphthalene-4-sulfonic acid | 84-86-6 | Piria’s acid, naphthionic acid | sulfonation 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 acid | 84-89-9 | Laurent’s acid, L acid, Purpurin acid | reduction of 1-nitronaphthalene-5-sulfonic acid. With NaOH, converts to 5-amino-1-naphthol ("purpurol"). |
| 1-Aminonaphthalene-6-sulfonic acid | 119-79-9 | 1,6-Cleve’s acid | sulfonation of 1-aminonaphthalene |
| 1-Aminonaphthalene-7-sulfonic acid | 119-28-8 | 1,7-Cleve’s acid | by-product in production of 1,6-Cleve’s acid, precursor to C.I. Acid Black 36 |
| 1-Aminonaphthalene-8-sulfonic acid | 82-75-7 | Peri acid | reduction of 1-nitroonaphthalene-8-sulfonic acid, precursor to C.I. Acid Blue 113 |
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.
| Isomer | CAS Registry Number | Alternative names | Preparative route and notes |
|---|---|---|---|
| 2-Aminonaphthalene-1-sulfonic acid | 81-16-3 | Tobias acid | Bucherer reaction of 2-hydroxynaphthalene-1-sulfonic acid with ammonium salts, precursor to C.I. Pigment Red 49 |
| 2-Aminonaphthalene-5-sulfonic acid | 81-05-0 | Dahl’s acid, Dressel acid, D acid | Desulfonation of 2-aminonaphthalene-1,5-disulfonic acid |
| 2-Aminonaphthalene-6-sulfonic acid | 93-00-5 | Bronner acid | Bucherer amination of 2-hydroxynaphthalene-6-sulfonic acid |
| 2-Aminonaphthalene-7-sulfonic acid | 494-44-0 | Amido F acid; Delta acid; Monosulphonic F acid | Bucherer amination of 2-hydroxynaphthalene-7-sulfonic acid |
| 2-Aminonaphthalene-8-sulfonic acid | 86-60-2 | Badische acid | Bucherer amination of 2-hydroxynaphthalene-8-sulfonic acid |
References
- ^ Gerald Booth "Naphthalene Derivatives" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. doi:10.1002/14356007.a17_009.