3-NITROBENZENESULFONIC ACID Chemical Properties

Melting point:

103-104℃

Density 

1.637

refractive index 

1.5380 (estimate)

Water Solubility 

Completely soluble in water

form 

solid

pka

-1.21±0.18(Predicted)

color 

White to Light yellow

CAS DataBase Reference

98-47-5(CAS DataBase Reference)

EPA Substance Registry System

Benzenesulfonic acid, 3-nitro- (98-47-5)

Safety Information

Risk Statements 

34

Safety Statements 

26-36/37/39

RIDADR 

2305

RTECS 

DB7190000

HazardClass 

8

PackingGroup 

II

HS Code 

2904990090

3-NITROBENZENESULFONIC ACID Usage And Synthesis

Chemical Properties

Crystals. Soluble in water and alcohol.

Uses

Organic synthesis. The sodium salt is a protective antireduction agent.

Uses

3-Nitrobenzenesulfonic acid is used primarily as a mild oxidizing agent or as a precursor for colorant intermediates. In the former case it is used in processing certain anthraquinone intermediates (e.g., amination of anthraquinone-1-sulfonic acid to give 1- aminoanthraquinone) or as a dye-printing auxiliary to obtain resist effects with, for example, vat dyes. Reduction of 3-nitrobenzenesulfonic acid (usually as a liquor) to the important metanilic acid is achieved with iron or by catalytic hydrogenation. The alternative reduction with zinc and alkali or with sodium amalgam yields hydrazobenzene-3,3'-disulfonic acid, which rearranges to benzidine-2,2' - disulfonic acid [117-61-3] on treatment with acid.

Production Methods

3-Nitrobenzenesulfonic acid is produced by dissolving nitrobenzene in 98 % sulfuric acid and heating to 80 ℃. Then 65 % oleum is added at this temperature, and the reaction is completed by heating for 9 h at 105 ℃ (higher temperatures are unsafe). After quenching the sulfonation mass in water, neutralizing with lime, and filtering off gypsum, the calcium salt of the product is converted to the sodium salt with sodium carbonate. After calcium carbonate has been removed by filtration, the sodium salt solution can be used directly or evaporated.

Safety Profile

A skin and severe eye irritant. Decomposes violently at about 200°. Mixture with sulfuric acid + sulfur trioxide may explode above 150°C. When heated to decomposition it emits toxic fumes of SOx and NOx. See also NITRO COMPOUNDS OF AROMATIC HYDROCARBONS and SULFONATES.

3-NITROBENZENESULFONIC ACID(98-47-5)Related Product Information

• Sodium 2-chloro-5-nitrobenzenesulfonate
• 4-CHLORO-3,5-DINITROBENZENESULFONIC ACID
• 4-NITRO-2-SULFOANILINE
• 2-Amino-4-nitrophenol-6-sulfonic acid
• ACID YELLOW 65
• (S)-(+)-Glycidyl nosylate
• 2-NITROTOLUENE-4-SULFONIC ACID
• ACID ORANGE 51
• 4-(4-Aminoanilino)-3-nitrobenzenesulphonic acid
• 4-Nitrotoluene-2-sulfonic Acid
• 4,4'-DINITROSTILBENE-2,2'-DISULFONIC ACID DISODIUM SALT
• 4-Nitro-4'-aminostilbene-2,2'-disulfonic acid
• Sodium 3-nitrobenzenesulphonate
• 4,4'-Dinitrostilbene-2,2'-disulfonic acid
• ACID YELLOW 99
• 4-CHLORO-3-NITROBENZENESULFONIC ACID, SODIUM SALT
• 2,6-DINITROTOLUENE-4-SULFONIC ACID
• 2-Amino-6-nitro-1-phenol-4-sulfonic acid