Question

The correct IUPAC name of the compound ${{(C{{H}_{3}}C{{H}_{2}})}_{2}}NC{{H}_{3}}$ is:
(A) N-ethyl-N-methyl ethanamine
(B) N, N-diethyl ethanamine
(C) N-methyl ethanamine
(D) N-ethyl ethanamine

Answer 1

Hint: We can use the suffix –amine to name the amine compounds. If the substituent groups are on nitrogen atoms, then we can show its position by using N-. Substituent groups need to be arranged in an alphabetical manner in IUPAC nomenclature.

Complete step by step solution:
Let’s draw the structure of the given compound to name it.

Now, first of all, we need to identify the functional group present in the compound if any. We can see that there is an amino-functional group present in the compound as nitrogen atom is bonded with three carbon atoms.
- Now, we will identify the longest chain of carbon atoms and we will use the suffix –amine to identify the presence of the amino group.
- We can see that there is a possibility of two carbon chains which is the longest possible chain of carbon atoms possible in this structure.
- So, we can write ‘ethanamine’ as it will describe the two-carbon chain and amino group. But we will also have to show other substituent groups on the nitrogen.
- We can see that there is one ethyl group and one methyl group is substituted on the nitrogen atom. Remember that we do not give numbering to the nitrogen atom in the nomenclature of amines. So, we will have to denote them by N-.
-We will adjust the order of writing the name of substituent groups in an alphabetical manner.
So, we can finalize the name of the compound as N-ethyl-N-methyl ethanamine.

Thus, the correct answer is (A).

Note: Do not forget that we cannot give numbering to the nitrogen atom, so we need to show the alkyl substituent groups by N-. We need to find the longest possible carbon atom chain as a parent chain, so we cannot use methenamine here as ethyl group is also present in the compound.