Naming Amines

Definition of Primary Amines:

Primary, Secondary and Tertiary Amines:

In general amine molecules can vary in size up to very long molecules most of which consist of carbon atoms attached to each other and also to hydrogen atoms. In addition to primary amines, there are other classes of amines such as secondary amines, tertiary amines and cyclic amines. In those cases, although the nitrogen atom (N) is present, the -NH₂ group that forms part of primary amines is not complete because in the cases of e.g. secondary and tertiary amines, one or more of the hydrogen atoms is replaced by a carbon bonded to other atoms (e.g. carbons and hydrogens).

The diagram shows that in the case of primary amines, the N is bonded to two Hs and one C whereas in the cases of secondary and tertiary amines the N is bonded to 2 and 3 Cs respectively.

In the cases of ...

• Primary amides, only one cardon atom is attached to the N. In that case the N is also attached to two Hs.
• Secondary amides, two carbon atoms are attached to the N.
• Tertiary amides, three carbon atoms are attached to the N.

Amines are named in several ways. The name of the compound is usually formed from either the prefix 'amino-' or the suffix: '-amine.'

The prefix 'N-' indicates which carbon atom the nitrogen atom is attached to.

In the following table of linear primary amines the nitrogen atom is attached to an end carbon, hence it is counted as a 'first' or 'one' carbon atom in all of these examples. Lists of some of the other names also used to refer to these specific simple linear primary amines are included in the table.

Names and Structures of simple Linear Primary Amines

The first 10 members of the homologous series of linear primary amines with the -amine (or '-amino') group attached to the first (= last) carbon atom are:

Why stop at ten carbon atoms (in the chain) ? It doesn't. There are more similar linear amines, or 1-aminoalkanes. We stopped here due to page width.

Important Note: *The synonyms indicated for compounds listed above are just some examples of alternative names found online and believed to have been used to refer to the substance indicated. They have not all been verified and may include common (non-scientific) names and trade names specific to particular suppliers. The purpose of these lists is to give a general indication of the range of names by which these amines are known.

Examples of simple Secondary Amines

Other members of this homologous series of secondary amines include dipropylamine, dibutylamine, dipentylamine, dihexylamine and so on.

Examples of simple Tertiary Amines

Other members of this homologous series of tertiary amines include tripropylamine, tributylamine, tripentylamine, trihexylamine and so on.

See also the related page about functional groups in organic molecules, which includes the nitrile group among others.

Note: This is one of many pages about types of organic compounds in our Organic Chemistry Section. Similar and related pages describe hydrocarbons, alkanes, haloalkanes, alkenes, alkynes, cycloalkanes, aromatic hydrocarbons (arenes), alcohols, esters, ethers, aldehydes, ketones, carboxylic acids, acid chlorides, acid anhydrides, azo dyes, amines, amides, nitriles, amino acids (chemistry), peptides, proteins (chemistry), polypeptides and others. If you need further information ask your chemistry tutor.