Like suffixes, prefixes are also of two types:
(i) Primary prefix. A primary prefix is used simply to distinguish cyclic from acyclic compounds. For example, in case of carbocyclic compounds, a primary suffix cyclo is used immediately before the word root. Thus,
(ii) Secondary prefix. In IUPAC system of nomenclature, certain groups are not considered as functional groups but instead are treated as substituents. These are called secondary prefixes and are added immediately before the word root (or the primary suffix in case of carbocyclic compounds) in alphabetical order to denote the substituent groups or the side chains.
The secondary prefixes for some groups which are always treated as substituent groups (regardless of the fact whether the organic compound is monofunctional or polyfunctional) are given below .
2–Fluoro–4–methoxypentane
