Aniline-2-sulfonic acid Property

Melting point:

300 °C

Boiling point:

363.26℃[at 101 325 Pa]

Density 

1.342 (estimate)

vapor pressure 

0Pa at 25℃

refractive index 

1.5500 (estimate)

storage temp. 

Keep in dark place,Inert atmosphere,Room temperature

solubility 

3.565g/L in organic solvents at 20 ℃

pka

2.48(at 25℃)

form 

Crystalline Powder

color 

White to beige

Water Solubility 

sparingly soluble

Merck 

14,6882

BRN 

1309204

InChIKey

ZMCHBSMFKQYNKA-UHFFFAOYSA-N

LogP

0 at 23℃

CAS DataBase Reference

88-21-1(CAS DataBase Reference)

NIST Chemistry Reference

Aniline-o-sulfonic acid(88-21-1)

EPA Substance Registry System

o-Aminobenzenesulfonic acid (88-21-1)

Safety

Hazard Codes 

C

Risk Statements 

34

Safety Statements 

26-36/37/39-45-28A

RIDADR 

UN 2585 8/PG 3

WGK Germany 

3

RTECS 

DB4727700

TSCA 

Yes

HazardClass 

8

PackingGroup 

III

HS Code 

29214200

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H314Causes severe skin burns and eye damage

Precautionary statements

P260Do not breathe dust/fume/gas/mist/vapours/spray.

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

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

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

P363Wash contaminated clothing before reuse.

Aniline-2-sulfonic acid Chemical Properties,Usage,Production

Chemical Properties

LIGHT BROWN FINE CRYSTALLINE POWDER

Definition

ChEBI: An aminobenzenesulfonic acid carrying an amino group at position 2.

Production Methods

2-Aminobenzenesulfonic acid (Aniline-2-sulfonic acid) is obtained from 2-nitrothiophenol by boiling in a mixture of dioxane and water (ratio 20:1) for seven hours; the yield is 86.7% of theory. The acid can also be produced as follows: 2-chloronitrobenzene is reacted with sodium disulfide in aqueous alcoholic solution to form 2,2'-dinitrodiphenyl disulfide. After having been dissolved in a mixture of hydrochloric acid and nitric acid this is oxidized with chlorine to form 2-nitrobenze- nesulfonyl chloride, which is then hydrolyzed with soda solution and finally reduced with iron turnings. Alternatively 2,2'-dinitrodiphenyl disulfide can first be reduced to 2,2'- diaminodiphenyl disulfide and then oxidized with hydrogen peroxide in aqueous sulfuric acid to 2-aminobenzenesulfonic acid.
2,2'- Diamino-diphenyldisulfide can also be arrived at by alkaline hydrolysis of benzothiazole or mercaptobenzothiazole, followed by oxidation with hydrogen peroxide. The additional oxidation leading to 2-aminobenzenesulfonic acid can be performed in alkaline solution. Thus the synthesis starting from benzothiazole can be carried out exclusively in alkaline solution in a single reactor. Yield: 70%, based on benzothiazole.

General Description

Light brown powder.

Air & Water Reactions

Soluble in water.

Reactivity Profile

Aniline-2-sulfonic acid is an amino acid. Reacts weakly with both acids and bases.

Fire Hazard

Flash point data for Aniline-2-sulfonic acid are not available, however Aniline-2-sulfonic acid is probably combustible.

Flammability and Explosibility

Non flammable

Purification Methods

Crystallise orthanilic acis from aqueous solution, containing 20mL of conc HCl per L, then crystallise it from distilled water, and dry it in a vacuum desiccator over Sicapent (m 315o). When an aqueous solution is chilled below 13.5o, the hydrated form of the acid is obtained. It is used for the determination of nitrite and nitrate. The S-benzylisothiuronium salt has m 137o (from H2O). [Wertheim Org Synth Coll Vol II 471 1943, Beilstein 14 H 681, 14 I 714, 14 II 429, 14 III 1896, 14 IV 2638.]