O-Tolidine Chemical Properties

Melting point:

128-131 °C(lit.)

Boiling point:

300.5 °C

Density 

0.9678 (rough estimate)

refractive index 

n20/D 1.341

Flash point:

244 °C

storage temp. 

?20°C

solubility 

2% HCl: 10 mg/mL, clear

pka

4.59±0.10(Predicted)

form 

powder (may contain lumps)

Colour Index 

37230

color 

light brown

Water Solubility 

Slightly soluble in water.

Merck 

14,9514

BRN 

2210640

Exposure limits

TLV-TWA none; carcinogenicity: A2 — Suspected Human Carcinogen (ACGIH), Animal Limited Evidence (IARC).

InChIKey

NUIURNJTPRWVAP-UHFFFAOYSA-N

NIST Chemistry Reference

[1,1'-Biphenyl]-4,4'-diamine, 3,3'-dimethyl-(119-93-7)

IARC

2B (Vol. 1, Sup 7) 1987

EPA Substance Registry System

3,3'-Dimethylbenzidine (119-93-7)

Safety Information

Hazard Codes 

T,N,F

Risk Statements 

45-68-51/53-22-11

Safety Statements 

53-45-61-16

RIDADR 

UN 3082 9/PG 3

WGK Germany 

3

RTECS 

DD1225000

F 

8

TSCA 

Yes

HazardClass 

6.1(b)

PackingGroup 

III

HS Code 

29215900

Hazardous Substances Data

119-93-7(Hazardous Substances Data)

MSDS

• Language:English Provider:C.I. 37230
• Language:English Provider:SigmaAldrich
• Language:English Provider:ACROS
• Language:English Provider:ALFA

O-Tolidine Usage And Synthesis

Description

2-Tolidine (orthotolidine, o-tolidine; not to be confused with o-toluidine) is an organic compound with the chemical formula (C6H4(CH3)NH2)2. Several isomers are known; the 3-tolidine derivative is also important commercially. It is a colorless compound although commercial samples are often colored. It is slightly soluble in water. It forms salts with acids, such as the hydrochloride, which is commercially available. 2-Tolidine can be produced by a benzidine rearrangement from a hydrazine derivative derived from 2-nitrotoluene.

Uses

2-Tolidine is a commercial aromatic amine used mainly for dye production. 2-Tolidine is an intermediate for the production of soluble azo dyes and insoluble pigments used particularly in the textile, leather and paper industries. 2-Tolidine was widely used as a reagent or indicator in analytical, clinical and forensic chemistry, such as in the analytical determination of gold, or determination of the chlorine level in swimming pool water.

Chemical Properties

LIGHT GREY-GREEN TO GREY POWDER

Chemical Properties

o-Tolidine is a white to reddish crystal or powder. Darkens on exposure to air. Often used in paste or wet cake form. Used as a basis for many dyes.

Uses

o-Tolidine is used extensively in the manufacture of dyes. It is also used as a reagentfor the analysis of gold and free chlorine inwater.

Uses

Sensitive colorimetric reagent for gold and for free chlorine in water.

Uses

3,3'-Dimethylbenzidine be used for preparation polyimide and epoxy resin material.

General Description

White to reddish crystals or crystalline powder or a light tan powder.

Air & Water Reactions

Insoluble in water.

Reactivity Profile

C.I. 37230 is sensitive to exposure to light. May be sensitive to prolonged exposure to air. A weak base that forms salts with hydrochloric acid or sulfuric acid. C.I. 37230 can be acetylated. Incompatible with strong agents .

Hazard

Eye, bladder and kidney irritant, bladder cancer, and methemoglobinemia. Possible carcinogen.

Health Hazard

The information on toxicity and carcinogenicity of o-tolidine is very little. o-Tolidineoften contains other biphenylamine contaminants. Its structure and chemical propertiesare similar to those of benzidine. The toxicproperties are therefore expected to be similar to those of benzidine.
o-Tolidine is absorbed into body throughthe skin, respiratory, and gastrointestinaltract. The acute oral and dermal toxicity wasmoderate in experimental animals. An oralLD50 value in rats is within the range of400 mg/kg.
o-Tolidine produced bladder cancer in testspecies. Also, cancers in other tissues werenoted in some animals. ACGIH lists thissubstance as a suspected human carcinogen.

Fire Hazard

Flash point data for C.I. 37230 are not available; however, C.I. 37230 is probably combustible.

Safety Profile

Confirmed carcinogen with experimental carcinogenic and tumorigenic data. Poison by intraperitoneal route. Moderately toxic by ingestion. Human mutation data reported. When heated to decomposition it emits toxic fumes of NOx.

Potential Exposure

Over 75% of o-tolidine is used as a dye and as an intermediate in the production of rubber products, dyestuffs, pigments and pesticides. Approximately 20% of o-tolidine is used in the production of polyurethane-based high-strength elastomers, coatings, and rigid plastics. o-Tolidine has also been used in small quantities in chlorine test kits by water companies and swimming pool owners. Used as a laboratory agent to detect blood.

Carcinogenicity

3,3′-Dimethylbenzidine is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.

Shipping

UN2811 Toxic solids, organic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required. UN3077 Environmentally hazardous substances, solid, n.o.s., Hazard class: 9; Labels: 9-Miscellaneous hazardous material, Technical Name Required.

Purification Methods

Dissolve the tolidine in *benzene by percolation through a column of activated alumina and crystallise it from *benzene/pet ether. [Beilstein 13 IV 410.]

Incompatibilities

Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides, strong reducing agents.

Waste Disposal

Dissolve in flammable solvent and spray into firebox of an incinera tor equipped with afterburner and scrubber. Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform with EPA regulations governing storage, transportation, treatment, and waste disposal.

O-Tolidine(119-93-7)Related Product Information

• ACID RED 114
• DIANIL BLUE 2R
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• CI 23790
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• Direct Blue 14
• 3,3'-DIMETHYLNAPHTHIDINE
• BENZOPURPURIN 4B
• N,N'-(3,3'-Dimethyl-4,4'-biphenyldiyl)bis(3-oxobutanamide)
• O-TOLUIDINE DISULFONIC ACID
• N-(3-Sulfopropyl)-3,3',5,5'-tetramethylbenzidine sodium salt
• TIMTEC-BB SBB003162
• DIRECT FAST RED 3B
• 3,3'-Dimethyl-4,4'-biphenylene diisocyanate
• ROSAZURIN B
• 3,3'-Dimethylbenzidine dihydrochloride
• Direct Blue 53
• O-TOLIDINE SULFONE