anilina

Anilina, or aniline (phenylamine), is an aromatic amine with the formula C6H5NH2. It is the simplest member of the aniline family, formed by replacing a hydrogen on benzene with an amino group. It typically appears as a colourless to yellowish liquid with a strong, characteristic odor. It is slightly soluble in water and highly soluble in many organic solvents; it is flammable and reacts with oxidizers. The substance is a weak base, forming anilinium salts with acids.

Industrial production usually relies on the catalytic hydrogenation of nitrobenzene, using hydrogen in the presence of catalysts such as Raney nickel, to give aniline after purification. Alternative routes include the reduction of nitroaromatic compounds derived from benzene or chlorobenzene, but the nitrobenzene route remains the principal industrial process.

Aniline is a versatile chemical precursor. It is used to manufacture many dyes and pigments, including various aniline dyes, and serves as a building block for rubber processing chemicals and agricultural products. It is also a precursor to polyurethane foams, via the production of methylene diphenyl diisocyanate (MDI), and to a range of other specialty chemicals and pharmaceuticals.

Safety and handling are important due to its toxicity. Exposure can cause methemoglobinemia and irritation of the eyes, skin, and respiratory tract; prolonged or high-level exposure may be harmful. It should be stored and transported under appropriate controls, away from oxidizers, and handled with adequate ventilation, protective clothing, and eye protection. Accidental spills require prompt containment and proper disposal.