nitril

Nitril, or nitrile, refers to a class of organic compounds containing the cyano group -C≡N. In systematic nomenclature, nitriles are named as alkyl or aryl nitriles, with the nitrile group present in many functional molecules. The nitrile group is linear in simple molecules and highly polar, contributing to relatively high boiling points for their size and good solvating ability in organic solvents.

Common examples include acetonitrile (CH3CN), acrylonitrile (CH2CHCN), and benzonitrile (C6H5CN). Nitriles range from simple gases to high-boiling liquids. They are typically poor bases and can act as polar aprotic solvents; their reactivity is dominated by the nitrile carbon, which can participate in hydrolysis, reduction, and various condensation reactions.

Industrial production of nitriles uses several routes. Acrylonitrile, one of the most important, is produced by ammoxidation of propylene. Other nitriles are generated by dehydration of amides or by hydrocyanation of alkenes followed by oxidation or hydrolysis. The choice of route depends on the target nitrile and its applications.

Applications include solvents (notably acetonitrile in chromatography), polymer precursors such as acrylonitrile for plastics and polyacrylonitrile fibers, and nitrile rubber (NBR). Nitrile-containing polymers are valued for strength, chemical resistance, and abrasion resistance. Nitrile gloves provide chemical resistance for industrial and medical use.

Safety and environmental considerations are important. Some nitriles are toxic and can irritate skin, eyes, and the respiratory system. Metabolic processing of certain nitriles can release cyanide, so safe handling, adequate ventilation, and proper disposal are advised.