Amines

Basic IUPAC Organic Nomenclature

Amines

Nomenclature

Formula

3D structure

Functional class name = alkylamines or alkanamines

Substituent suffix = -amine e.g. ethylamine

Substituent prefix = amino- e.g. aminoethane

Structural unit (depending on R, R' and R")

primary amines contain R-NH₂
secondary amines contain R₂NH
tertiary amines contain R₃N.

There are slight differences between amines depending on whether they are primary, secondary or tertiary (based on number of R groups attached to the N)

Primary amines

Primary amines have one alkyl group attached to the N.
The root name is based on the longest chain with the -NH₂ attached.
The chain is numbered so as to give the amine unit the lowest possible number.
The amine suffix is appended to the appropriate alkyl root or alkana- root.

Functional group is an amine, therefore suffix = -amine
Hydrocarbon structure is an alkane therefore -ane
The longest continuous chain is C4 therefore root = but
The first point of difference rule requires numbering from the right as drawn to make the amine group locant 2-

butan-2-amine or 2-butylamine
(or sec-butylamine)

CH₃CH₂CH(NH₂)CH₃

Secondary amines

Secondary amines have two alkyl groups attached to the N.
The root name is based on the longest chain with the -NH attached.
The chain is numbered so as to give the amine unit the lowest possible number.
The other alkyl group is treated as a substituent, with N as the locant.
The N locant is listed before numerical locants, e.g. N,2-dimethyl....
The amine suffix is appended to the appropriate alkyl root or alkana- root.

Functional group is an amine, therefore suffix = -amine
Hydrocarbon structure is an alkane therefore -ane
The longest continuous chain is C2 therefore root = eth

N-methylethylamine
or
N-methylethanamine

CH₃NHCH₂CH₃

Tertiary amines

Tertiary amines have three alkyl group attached to the N.
The root name is based on the longest chain with the -N attached.
The chain is numbered so as to give the amine unit the lowest possible number.
The other alkyl groups are treated as substituents, with N as the locant.
The N locant is listed before numerical locants, e.g. N,2-dimethyl....
The amine suffix is appended to the appropriate alkyl root or alkana- root.

Functional group is an amine, therefore suffix = -amine
Hydrocarbon structure is an alkane therefore -ane
The longest continuous chain is C1 therefore root = meth

Name : N,N-dimethylmethylamine
or
N,N-dimethylmethanamine
or
trimethylamine

(CH₃)₃N