A tertiary amine has all three H atoms substituted with R groups:

Naming simple amines is straightforward: name the R groups as substituents and then add the suffix –amine, using numerical suffixes on the substituent names as necessary. This amine is diethylamine.

This amine is ethyldipropylamine.

Example 11

Name this amine.

Solution

This amine has a methyl group, an ethyl group, and a propyl group. Listing the names in alphabetical order, this amine is ethylmethylpropylamine.

Test Yourself

Name this amine.

Answer

triethylamine

As with NH₃, the N atom in amines can accept a proton onto the lone electron pair on the N atom. That is, amines act as Brønsted-Lowry bases (i.e., proton acceptors):

The amine becomes an ion, the organic counterpart of the ammonium (NH₄⁺) ion.

 The weakness of amines is about the same as that of carboxylic acids. N-containing organic compounds are very common in nature, and they all act as weak bases. Some of these compounds have rather complicated structures. Figure 1.1 “Some Naturally Occurring N-Containing Compounds” shows some N-containing substances that you may recognize.

Figure 1.1 Some Naturally Occurring N-Containing Compounds