nitrilo

Nitrilo, in chemistry often referred to as a nitrile, designates a class of organic compounds that contain the cyano group, a carbon triple bonded to nitrogen (-CN). The general formula for simple nitriles is R-CN, where R is an alkyl or aryl group. The cyano group is a polar, relatively small substituent that withdraws electron density, giving nitriles distinctive physical and chemical properties such as relatively high dipole moments and varying degrees of water miscibility depending on the R group.

Common examples of nitriles include acetonitrile (CH3CN), benzonitrile (C6H5CN), and acrylonitrile (CH2=CH-CN). Many nitriles are colorless liquids or solids at room temperature. Acetonitrile, in particular, is a widely used polar aprotic solvent in analytical chemistry and organic synthesis, notable for its high dielectric constant and low nucleophilicity. Acrylonitrile is a key monomer for the production of polyacrylonitrile fibers used in textiles and various plastics, while benzonitrile serves as an intermediate in pharmaceutical and agrochemical synthesis.

Production methods for nitriles vary. Industrial routes include the ammoxidation of alkenes or alkanes (for example, propylene to acrylonitrile) and the dehydration or cyanation of corresponding amides or aldehydes to form nitriles. Nitriles also arise as intermediates in various catalytic processes and can be prepared from suitable precursors in laboratory settings.

Applications of nitriles span solvents, chemical intermediates, polymer precursors, and specialty chemicals. Nitrile-containing polymers such as polyacrylonitrile and nitrile rubber (NBR) are notable for their mechanical and chemical resistance. Safety concerns center on their toxicity and potential release of cyanide species upon metabolism, requiring appropriate handling, ventilation, and waste management.