| Identification | Back Directory | [Name]
4-hydroxynaphthalene-2-sulphonic acid | [CAS]
3771-14-0 | [Synonyms]
4-hydroxynaphthalene-2-sulfonic acid
4-Hydroxy-2-naphthalenesulfonic acid
4-hydroxynaphthalene-2-sulphonic acid
2-Naphthalenesulfonic acid, 4-hydroxy- | [EINECS(EC#)]
223-212-7 | [Molecular Formula]
C10H8O4S | [MDL Number]
MFCD00021505 | [MOL File]
3771-14-0.mol | [Molecular Weight]
224.23 |
| Hazard Information | Back Directory | [Chemical Properties]
1-Hydroxynaphthalene-3-sulfonic acid [3771-14-0]. (4-hydroxynaphthalene-2- sulfonic acid), C10H8O4S, Mr 224.2, and its salts are very soluble in water. Coupling with diazo compounds occurs in the 2-position with weak diazo compounds, but in the 4-position with strong diazo compounds such as diazotized nitroanilines. Heating with ammonia at 170℃ gives 1,3-naphthalenediamine. | [Uses]
1-Hydroxynaphthalene-3-sulfonic acid is used as a coupling component for the production of direct dyes. | [Preparation]
1-Aminonaphthalene-3-sulfonic acid is heated with dilute sulfuric acid by using high-pressure steam to maintain a pressure of 1 MPa for 20 h. After cooling, screening, and adding salt to the hot liquor, the sodium salt crystallizes on cooling and is isolated in 80 % yield. |
|
|