1-Amino-2-naphthol-4-sulfonic acid Property

Melting point:

290 °C (dec.)(lit.)

Density 

1.4338 (rough estimate)

refractive index 

1.6500 (estimate)

storage temp. 

Store below +30°C.

solubility 

DMSO (Slightly), Methanol (Slightly)

pka

-0.49±0.40(Predicted)

form 

Powder

color 

White to light pink

Water Solubility 

insoluble

Merck 

14,454

BRN 

2697469

Stability:

Stable. Incompatible with strong bases, acid chlorides, acid anhydrides, strong oxidizing agents.

InChIKey

RXCMFQDTWCCLBL-UHFFFAOYSA-N

CAS DataBase Reference

116-63-2(CAS DataBase Reference)

NIST Chemistry Reference

1-Naphthalenesulfonic acid,4-amino-3-hydroxy-(116-63-2)

EPA Substance Registry System

1-Naphthalenesulfonic acid, 4-amino-3-hydroxy- (116-63-2)

Safety

Hazard Codes 

Xi

Risk Statements 

36/37/38

Safety Statements 

37/39-26

RIDADR 

3265

WGK Germany 

3

RTECS 

QK1292000

TSCA 

Yes

HazardClass 

IRRITANT

PackingGroup 

III

HS Code 

29222100

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P405Store locked up.

1-Amino-2-naphthol-4-sulfonic acid Chemical Properties,Usage,Production

Chemical Properties

1-Amino-2-hydroxynaphthalene-4-sulfonic acid [116-63-2]. (4-amino-3-hydroxynaphthalene-1-sulfonic acid), B€oniger acid, C10H9NO4S, Mr 239.2, is obtained as white or gray needles of the hemihydrate, which is only sparingly soluble in hot water. The alkali-metal salts are soluble in water, but the solutions slowly oxidize in air. Oxidation with nitric acid gives 1,2- naphthoquinone-4-sulfonic acid.

Uses

4-Amino-3-hydroxy-1-naphthalenesulfonic acid is used as mordant dyes and acid dyes intermediate.

Uses

1-Amino-2-naphthol-4-sulfonic acid can be used in determination of phosphate.

Definition

ChEBI: 4-amino-3-hydroxynaphthalene-1-sulfonic acid is a naphthalenesulfonic acid and an aminonaphthalene. It has a role as a mutagen. It is functionally related to a 2-naphthol.

Production Methods

2-Naphthol is dissolved in dilute aqueous sodium hydroxide and precipitated in finely divided form by addition of sulfuric acid at 5℃. Sodium nitrite solution is added to the slightly alkaline suspension, followed by sulfuric acid to effectthe nitrosation while the temperature is held at 5 – 8℃. The suspension of 1-nitroso2-naphthol is neutralized with aqueous sodium hydroxide; a solution of sodium bisulfite is then added. The temperature is allowed to rise to 20℃, and the soluble bisulfite addition complex is formed. Excess sulfuric acid is then added and the temperature is raised to 40℃, whereupon reductive rearrangement takes place and the product slowly crystallizes at 50℃. Filtration and washing give the product as a 25 % paste in 80 % yield. All plant items and reactants must be free from iron to avoid complex formation.

Purification Methods

Purify it by warming 15g of the acid, 150g of NaHSO3 and 5g of Na2SO3(anhydrous) with 1L of water to ca 90o, shaking until most of the solid had dissolved, then filtering hot. The precipitate obtained by adding 10mL of conc HCl to the cooled filtrate is collected, washed with 95% EtOH until the washings are colourless, and is dried under vacuum over CaCl2. It is stored in a dark-coloured bottle, in the cold [Chanley et al. J Am Chem Soc 74 4347 1952]. [Beilstein 14 IV 2825.]