methylanilines

Methylanilines, also known as toluidines, are a group of organic compounds with the chemical formula CH3C6H4NH2. They are aromatic amines, meaning they consist of an aniline molecule where one of the hydrogen atoms on the benzene ring has been replaced by a methyl group. Methylanilines are isomers, differing in the position of the methyl group relative to the amino group on the benzene ring. The three common isomers are ortho-toluidine (2-methylaniline), meta-toluidine (3-methylaniline), and para-toluidine (4-methylaniline).

These compounds are typically colorless to yellowish liquids or solids with a characteristic amine odor. They are soluble in organic solvents like ethanol and ether, and sparingly soluble in water. Methylanilines are weak bases due to the presence of the amino group. They undergo reactions typical of aromatic amines, such as diazotization, acylation, and alkylation.

Industrially, methylanilines are important intermediates in the synthesis of dyes, pigments, pharmaceuticals, pesticides, and other organic chemicals. For example, para-toluidine is used in the production of azo dyes and certain sulfonamides. Ortho-toluidine finds applications in the synthesis of herbicides and rubber chemicals. Meta-toluidine is also used in dye manufacturing and as a precursor for some specialty chemicals. Due to their potential toxicity and carcinogenicity, especially ortho-toluidine, appropriate safety precautions are necessary during their handling and use. Exposure can occur through inhalation, skin absorption, or ingestion.