General Description
A clear colorless liquid. Flash point below 200°F. Vapors heavier than air. Toxic by inhalation, ingestion, and skin absorption in high concentrations or under prolonged exposures. Used in the manufacture of organic chemicals. Density about 8 lb/gal.
Reactivity Profile
M-TOLUIDINE(108-44-1) neutralizes acids in exothermic reactions to form salts plus water. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. May generate hydrogen, a flammable gas, in combination with strong reducing agents such as hydrides. Can react vigorously with oxidizing reagents. Emits toxic fumes of oxides of nitrogen when heated to decomposition [Lewis, 3rd ed., 1993, p. 1253].
Air & Water Reactions
Slightly soluble in water.
Health Hazard
Absorption of toxic quantities by any route causes cyanosis (blue discoloroation of lips, nails, skin); nausea, vomiting, and coma may follow. Repeated inhalation of low concentrations may cause pallor, low-grade secondary anemia, fatigability, and loss of appetite. Contact with eyes causes irritation.
Fire Hazard
Special Hazards of Combustion Products: Toxic oxides of nitrogen and flammable vapors may form in fire.
Description
m-Toluidine is an aromatic amine compound widely used as a dye raw material, but the aromatic amines of m-Toluidine and o-anisidine have shown damage to the bladder mucosa and potential carcinogenicity[2]. In addition, m-Toluidine monomers can be synthesized into poly(o-toluidine) by chemical oxidation polymerization in acidic medium, which has anti-corrosion properties for low-carbon steel in 3.5% NaCl[3]. Aniline-m-Toluidine copolymers can also be used to prepare NiO-based multicolor electrochromic films, and the composite films can achieve multiple color changes such as yellow, green, blue and dark brown[4].
Chemical Properties
Colorless liquid. Slightly soluble
in water; soluble in alcohol or ether. Combustible.
Preparation
m-Toluidine can be obtained by hydrocracking of 2,3-dimethylaniline in the presence of an alkaline nickel-magnesium catalyst.[1]
Flammability and Explosibility
Nonflammable
Carcinogenicity
In an 18-month carcinogenicity diet evaluation in maleCD
rats (8000 ppm for 3 months, and then 4000 ppm for additional
15 months; or 16,000 ppm for 3 months, and then 8000
for additional 15 months), and male and female CD-1 mice
(16,000 ppm for 5 months, and then 4000 ppm in males and
8000 ppm in females for additional 13 months; or
32,000 ppm in both sexes for 5 months, and then
8000 ppm in males and 16,000 ppm in females for additional
13 months), there was no evidence of a significant increase of
incidence of any kind of tumor in the rats, and only a
significant increase in liver tumors in male mice.
Purification Methods
It can be purified as for aniline. Twice-distilled, m-toluidine is converted to the hydrochloride using a slight excess of HCl, and the salt is fractionally crystallised from 25% EtOH (five times), and from distilled water (twice), rejecting, in each case, the first material that crystallised out. The amine is regenerated and distilled as for o-toluidine. The benzoyl derivative has m 125o (from EtOH). [Berliner & May J Am Chem Soc 49 1007 1927, Beilstein 12 H 853, 12 I 397, 12 II 463, 12 III 1949, 12 IV 1813.]
References
[1] TADASHI MATSUMOTO; Hiroaki T; Y Tachibana. DEMETHYLATION OF 2,3-XYLIDINE TO m-TOLUIDINE[J]. Chemistry Letters, 1978, 7 1: 435-438. DOI:10.1246/CL.1978.435.
[2] TAKESHI TOYODA. Mucosal damage and γ-H2AX formation in the rat urinary bladder induced by aromatic amines with structures similar to o-toluidine and o-anisidine[J]. Archives of Toxicology, 2023, 97 12: 3197-3207. DOI:10.1007/s00204-023-03606-0.
[3] JIAWEI ZHANG; Sensen Z; Ying Li. Preparation, Characterization and Corrosion Evaluation of Poly(o-toluidine), Poly(m-Toluidine), and Poly(p-Toluidine) Blended with Waterborne Polyurethane[J]. JOM, 2018, 70 11: 2660-2666. DOI:10.1007/s11837-018-3122-7.
[4] HONGQIN ZHAO . An efficient multi-color electrochromic electrode based on nanocomposite of aniline and o-toluidine copolymer with nickel oxide[J]. Solar Energy Materials and Solar Cells, 2023, 257: Article 112374. DOI:10.1016/j.solmat.2023.112374.
