butyyli

Butyyli is the Finnish term for the butyl substituent, a hydrocarbon group derived from butane by removing one hydrogen, giving the C4H9 moiety. In standard IUPAC nomenclature, the four constitutional isomers are butan-1-yl (n-butyl), butan-2-yl (sec-butyl), 2-methylpropyl (isobutyl), and 1,1-dimethylethyl (tert-butyl). The different isomers exhibit distinct steric and electronic properties that influence the behavior of the molecules they are part of.

Butyl groups appear in a wide range of organic compounds. They are common in esters such as butyl acetate and in alcohols such as n-butanol, sec-butanol, isobutanol, and tert-butanol. They also appear in ethers like tert-butyl methyl ether, and in polymers and rubbers, most notably polyisobutylene, the principal component of many butyl rubbers.

In synthesis and formulation, butyl substituents are introduced by alkylation or through reagents that deliver the desired butyl group. The tert-butyl group is notably bulky and can serve as a protecting group or influence the volatility and solubility of a molecule; the other isomers provide different steric profiles.

Safety and handling: hydrocarbon solvents containing butyl groups are typically flammable and may cause irritation; standard safety practices apply. See also: butyl group, butyl acetate, butanol, polyisobutylene, tert-butyl group.