Nomenclature
According to IUPAC nomenclature, "isobutyl", "sec-butyl", and "tert-butyl" are all retained names.
| Skeletal formula | Common name | IUPAC name | Systematic name | Alternate notation |
|---|---|---|---|---|
| n-butyl | butyl | butyl | butan-1-yl | |
| isobutyl | isobutyl | 2-methylpropyl | 2-methylpropan-1-yl | |
| sec-butyl | sec-butyl | 1-methylpropyl | butan-2-yl | |
| tert-butyl | tert-butyl | 1,1-dimethylethyl | 2-methylpropan-2-yl |
Butyl is the largest substituent for which trivial names are commonly used for all isomers.
The butyl group's carbon that is connected to the rest (R) of the molecule is called the RI or R-prime carbon. The prefixes sec (from "secondary") and tert (from "tertiary") refer to the number of additional side chains connected to the first butyl carbon. The prefix "iso" (from "isomer") means "equal" while the prefix 'n-' stands for "normal".
Read more about this topic: Butyl