butyl - Nomenclature and examples, Other examples, Etymology

CH₃CH₂CH₂CH₂–. A four-carbon aliphatic group. In addition to the form given, there are three other isomers: isobutyl (CH₃)₂CH–CH₂–; secondary butyl (CH₃)(C₂H₅)CH–; and tertiary butyl (CH₃)₃C–.

In organic chemistry, butyl is a four-carbon alkyl substituent with chemical formula -C4H9 .

Nomenclature and examples

Each of the two isomers of butane give rise to two isomers of monosubstituted butanes.

Examples n-butanol, also known as 1-butyl alcohol or 1-hydroxybutane: CH3CH2CH2CH2OH sec-butyl bromide, also known as 2-butyl bromide and 2-bromobutane: CH3CHBrCH2CH3

The second, branched isomer of butane, isobutane can also be substituted at either terminal methyl or internal carbon atoms, giving rise to "isobutyl" and "tertiary butyl" derivatives, respectively.

Examples iso-butyl bromide, also known as 1-bromo-2-methylpropane: (CH3)2CHCH2Br tert-butyl bromide, also known as 2-bromo-2-methylpropane: (CH3)3CBr

Butyl is the largest substituent for which trivial names are commonly used for all isomers.

Other examples

This is methyl tertiary butyl ether (an ether).

Etymology

As the number of carbons in an alkyl chain increases, butyl is the last to be named historically instead of through Greek numbers.