There isn’t space here to explain all the rules for giving systematic names for compounds— they fill several desperately dull volumes, and there’s no point knowing them anyway since computers will do the naming for you. What we will do is to explain the principles underlying systematic nomenclature. You should understand these principles because they provide the basis for the names used by chemists for the vast majority of compounds that do not have their own trivial names. Systematic names can be divided into three parts: one describes the hydrocarbon frame work, one describes the functional groups, and one indicates where the functional groups are attached to the skeleton. You have already met the names for some simple fragments of hydrocarbon framework (methyl, ethyl, propyl). Adding a hydrogen atom to these alkyl fragments and changing -yl to -ane makes the alkanes and their names. You should hardly need reminding of their structures:

The name of a functional group can be added to the name of a hydrocarbon framework either as a suffix or as a prefix. Some examples follow. It is important to count all of the car bon atoms in the chain, even if one of them is part of a functional group: pentanenitrile is actually BuCN.

Compounds with functional groups attached to a benzene ring are named in a similar way.