Aliphatic amines containing four or more carbon atoms show chain isomerism as branched and straight chain alkyl groups can be attached to the nitrogen atom.
Example: Butan-1-amine, 2-Methylpropan-1-amine, and 2 Methylpropan-2-amine are chain isomers.
2. Position Isomerism
The amino group can be bonded to different carbon atoms of the alkyl group.
Example: Propan-1-amine and Propan-2-amine
Primary, secondary and tertiary amines having the same molecular formula are isomers. This isomerism is functional isomerism because different alkyl groups (functional groups) are present in the molecules and give rise to isomerism
In amines metamerism, a type of isomerism in which different alkyl groups are attached to the Nitrogen atom of the amino group exists(molecular formula for isomers is same).
Example: Diethylamine, Methyl-n-propylamine, and Isopropylmethylamine are metamers.
5. Chiral amines
Nitrogen atom undergoes sp3 hybridisation. Hence secondary and tertiary amines have a chiral nitrogen atom. But chiral amines cannot be resolved. This is because the two enantiomeric forms rapidly interconvert and it is very difficult to isolate a pure sample of either enantiomer.