Introduction to Organic Nomenclature: Functional Groups, Prefix Only (i)

Basic Organic Nomenclature

An Introduction

Dave Woodcock,
Associate Professor Emeritus UBC (Okanagan)
©1996,2000, 2008

3. Functional Groups with Prefix Only (i)

Index

Most functional groups are named by using either a suffix or a prefix. However a few functional groups are only named as prefixes, which means that the rules already learned for using prefixes can immediately be adopted for these such compounds.

The following table shows a set of functional groups named only as prefixes, and the corresponding prefix.

Functional groups expressed only as prefixes.
Functional Group	IUPAC Prefix	Family Name
F	fluoro	fluoroalkane
Cl	chloro	chloroalkane
Br	bromo	bromoalkane
I	iodo	iodoalkane
NO₂	nitro	nitroalkane
N₃	azido	azidoalkane
OR*	alkoxy	alkoxyalkane (aka ether)

* In this function, the R represents an alkyl group and is the only one of these groups which needs to be discussed further.

Examples of the use of these prefixes (except alkoxy)

Examples of Functional groups expressed only as prefixes.
Compound	IUPAC Name	Molecular Model
CH₃F	Fluoromethane
CH₃NO₂	Nitromethane
CH₃CH₂N₃	Azidoethane
CH₂Cl₂	Dichloromethane
CF₃CCl₂H	2,2-Dichloro-1,1,1-trifluoroethane
	2-Iodobutane
	Bromocyclohexane
	2-Chlorospiro[4.5]decane

When alkyl branches and or more than one group named by a prefix are present in the same molecule, the several prefixes are intermixed and listed in alphabetical order.

Examples: