1-Naphthol-4-sulfonic acid

Product Name1-Naphthol-4-sulfonic acid
CAS84-87-7
MFC10H8O4S
MW224.23
EINECS201-568-4
MOL File84-87-7.mol

Chemical Properties

Melting point	170℃
Boiling point	335.63°C (rough estimate)
Density	1.4643 (rough estimate)
refractive index	1.7040 (estimate)
pka	0.73±0.40(Predicted)
form	solid
form	solid
color	white to yellow
InChI	InChI=1S/C10H8O4S/c11-9-5-6-10(15(12,13)14)8-4-2-1-3-7(8)9/h1-6,11H,(H,12,13,14)
InChIKey	HGWQOFDAUWCQDA-UHFFFAOYSA-N
SMILES	C1(S(O)(=O)=O)=C2C(C=CC=C2)=C(O)C=C1
CAS DataBase Reference	84-87-7(CAS DataBase Reference)
EPA Substance Registry System	1-Naphthalenesulfonic acid, 4-hydroxy- (84-87-7)

MSDS

Provider	Language
4-Hydroxy-1-naphthalenesulfonic acid	English

Usage And Synthesis

Chemical Properties

Transparent flake crystal. soluble in water. 1-Hydroxynaphthalene- 4 -sulfonic acid [84-87-7]. (4-hydroxynaphthalene-1-sulfonic acid), Nevile and Winther’s acid, NW acid, C10H8O4S, Mr 224.23, and its salts are water soluble, but the sodium salt may be precipitated from solution by salting out. Coupling with diazo compounds takes place in the 2-position. Nitration yields 2,4-dinitro-1-naphthol, whereas nitrosation gives 2-nitroso-1-hydroxynaphthalene-4-sulfonic acid. Sulfonation leads to a mixture of 1-hydroxynaphthalene-2,4-di- and 2,4,7- trisulfonic acids.

Uses

1-Naphthol-4-sulfonic acid is used as an intermediate of azo dyes to prepare dyes such as direct copper blue BR and 2R, direct violet RB, acid red B and acid medium jujube red B

Preparation

After drying under vacuum, the resulting filter cake contains 1-naphthol-4-sulphonic acid in a yield of 92% of theory and <0.5% 1-naphthol-2-sulphonic acid and 3% of 1-naphthol-2,4-disulphonic acid based on the weight of 1-naphthol-4-sulphonic acid.

Synthesis

1-Naphthol-4-sulfonic acid was synthesized by addition, hydrolysis and acid precipitation of sodium 1,4-aminonaphthalene sulfonate.

Preparation Products And Raw materials

Raw materials

Sodium bisulfite Naphthionic acid

Preparation Products

disodium 3-[[4'-[(6-amino-1-hydroxy-3-sulphonato-2-naphthyl)azo]-3,3'-dimethoxy[1,1'-biphenyl]-4-yl]azo]-4-hydroxynaphthalene-1-sulphonate C.I. 14720 Direct Blue 151 disodium 3-[[4'-[[6-amino-1-hydroxy-3-sulphonato-2-naphthyl]azo]-3,3'-dimethoxy[1,1'-biphenyl]-4-yl]azo]-4-hydroxynaphthalene-1-sulphonate sodium 3-[[4-(benzoylethylamino)-2-methylphenyl]azo]-4-hydroxynaphthalene-1-sulphonate sodium 4-hydroxy-3-[[3-(phenylsulphamoyl)-p-tolyl]azo]naphthalenesulphonate 3-[(5-Chloro-2-hydroxy-3-sulfophenyl)azo]-4-hydroxy-1-naphthalenesulfonic acid disodium salt 5-Amino-4-hydroxy-3-[[4'-[(1-hydroxy-4-sulfonaphthalen-2-yl)azo]-3,3'-dimethyl[1,1'-biphenyl]-4-yl]azo]-2,7-naphthalenedisulfonic acid trisodium salt Acid Red 374 4,4'-[(2-Methyl-5-sodiosulfo-1,3-phenylene)bis[azo(4,6-diamino-3,1-phenylene)azo]]bis[naphthalene-1-sulfonic acid sodium] salt BENZOAZURINE BRILLIANT PURPURIN R THIAZINE RED Acid Violet 131 NAPHTHALENE SCARLET B Aluminium, 7-hydroxy-8-[(4-sulfo-1-naphthalenyl)azo]-1,3-naphthalenedisulfonic acid complex Mordant Violet 2 DIRECTVIOLET32 disodium (3Z)-3-[[4-(4-anilino-3-sulfonato-phenyl)diazenylnaphthalen-1-yl]hydrazinylidene]-4-oxo-naphthalene-1-sulfonate 3-[[2-[(N-Ethyl-N-phenylamino)sulfonyl]phenyl]azo]-4-hydroxy-1-naphthalenesulfonic acid sodium salt 6-Amino-4-hydroxy-5-[[4'-[(1-hydroxy-4-sodiosulfo-2-naphthalenyl)azo]-1,1'-biphenyl-4-yl]azo]naphthalene-2-sulfonic acid sodium salt OXAMINE BLUE 4R