2-Nitrotoluene

Description

2-Nitrotoluene is a light yellow to darker yellow-green liquid. It is used for the synthesis of a variety of industrial products. These include to synthesise agricultural and rubber chemicals, azo and sulphur dyes, and dyes for cotton, wool, silk, leather, and paper. O-nitrotoluene decomposes on contact with strong oxidants, reducing agents, acids, or bases producing toxic fumes, nitrogen oxides, and carbon monoxide.

Chemical properties

Nitrotoluene is formed in 3 isomeric forms. The o-and m-forms are yellow liquids or solids. The p-form is a pale yellow crystalline solid. All have weak aromatic odors. The Odor Thresholds are: 0.05 mg/L (o-isomer); 1.74 ppm (m-isomer).

Physical properties

Clear, colorless to pale yellowish combustible liquid with a faint, aromatic odor. May darken on exposure to air.

The Uses of 2-Nitrotoluene

2-Nitrotoluene is used as an intermediate for the o-toludine synthesis, which finds application in the dyestuff industry. It is employed as a reagent in detecting and photometric determining oxidizing agent. It is also used in the determination of prussic acid content in the air. It acts as a precursor to prepare 2-amino-4-chlorotoluene, 2-amino-6-chlorotoluene, nitrotoluenesulfonic acids and toluene nitrosulfonic chlorides. It acts as a nitrogen supplement in the culture medium of pseudomonas sp. strain ClS1. It acts as a carbon and energy supplement in the culture medium of Pseudomonas sp. strain JS42.

Definition

ChEBI: 2-nitrotoluene is a mononitrotoluene that is toluene carrying a nitro substituent at position 2. It has a role as an environmental contaminant and a carcinogenic agent.

Preparation

2-Nitrotoluene was synthesized by nitration of toluene with mixed acid, A mixture of mononitrotoluene isomers can be prepared from the nitration of toluene between -10 oC and 30 oC. Lower temperatures result in little or no reaction, while higher temperatures will result in double nitration forming dinitrotoluenes.

General Description

Light yellow oily liquid with a characteristic odor of aromatic nitro compounds. Sinks in water. Derived from toluene by nitration and separation by fractional distillation. Flash point 223°F.

Air & Water Reactions

Insoluble in water.

Reactivity Profile

2-Nitrotoluene is toxic by inhalation, ingestion and skin aborption, targeting the blood, central nervous system, skin, and gastrointestinal tract. Symptoms include, anoxia, weakness or dizziness, nausea and vomiting. If 2-Nitrotoluene contacts the eye, the eye should be irrigated immediately. If 2-Nitrotoluene contacts the skin, the area should be washed with soap. If inhaled, respiratory support should be administered. Finally, if ingested, medical attention should be sought. 2-Nitrotoluene also reacts with sulfuric acid, sodium hydroxide, hydrogen, sodium, tetranitromethane, reducing agents and strong oxidizers. 2-Nitrotoluene is very heat sensitive.

Hazard

Toxic by inhalation, ingestion, skin absorption. Methemoglobinemia. Probable carcinogen.

Health Hazard

INHALATION, INGESTION, OR SKIN: Headache, flushing of face, dizziness, dyspnea (difficult breathing), cyanosis, nausea, vomiting, muscular weakness, increased pulse and respiratory rate, irritability, and convulsions. SKIN: Irritation.

Safety Profile

Confirmed carcinogen. A poison. Moderately toxic by ingestion. Mucous membrane effects by inhalation. Mutation data reported. Combustible when exposed to heat or open flame. To fight fire, use water spray, fog, foam, CO2. Potentially explosive reaction with alkali (e.g., sodmm hydroxide). When heated to decomposition it emits toxic fumes of NOx. See also other methylnitrobenzene entries and NITRO COMPOUNDS OF AROMATIC HYDROCARBONS.

Potential Exposure

The nitrotoluenes are used in the production of toluidines and other dye intermediates. All isomers are used in manufacture of agriculture and rubber chemicals and in various dyes.

Carcinogenicity

o-Nitrotoluene is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals and supporting data on mechanisms of carcinogenesis.

Environmental Fate

Biological. Robertson et al. (1992) reported that toluene dioxygenases from Pseudomonas putida F1 and Pseudomonas sp. Strain JS 150 oxidized the methyl group forming 2-nitrobenzyl alcohol.

Shipping

UN1664 Nitrotoluenes, (o-; m-; p-), Hazard Class: 6.1; Labels: 6.1-Poisonous materials.

Purification Methods

Crystallise 2-nitrotoluene (repeatedly) from absolute EtOH by cooling in a Dry-ice/alcohol mixture. Further purify it by passing an alcoholic solution through a column of alumina. [Beilstein 5 IV 845.]

Incompatibilities

Decomposes on contact with strong oxidizers; strong acids; reducing agents; strong bases; ammonia, amines producing toxic fumes, causing fire and explosion hazard. Heat above 190C may cause explosive decomposition. Attacks some plastics, rubbers, and coatings.

Waste Disposal

Controlled incineration-care must be taken to maintain complete combustion at all times. Incineration of large quantities may require scrubbers to control the emission of nitrogen oxides.