The IUPAC name of the following amine is

The correct answer is Option (3) → N,N-Dimethylmethanamine

Amines have both common names and IUPAC names:

• Common name: the alkyl groups are listed, followed by “amine” (for example, trimethylamine).

• IUPAC name: the amine is named as an alkanamine. In a secondary or tertiary amine, the largest alkyl group gives the parent name, and the other groups on nitrogen are written as prefixes with the locant N.

For example, \( \ce{CH3NHC2H5} \) is N-methylethanamine, and \( \ce{(CH3)2N-C2H5} \) is N,N-dimethylethanamine.

In the given compound, all three groups are methyl. One of them is taken as the parent (methanamine), and the other two are on nitrogen. So the IUPAC name is N,N-dimethylmethanamine.

Why the other options are incorrect

• Option (1) Trimethylamine — Incorrect. Trimethylamine is the common name of this compound, not its IUPAC name.

• Option (2) Dimethylmethylamine — Incorrect. This is neither the common name nor the IUPAC name: it mixes the common ending “methylamine” with prefixes, and the N locants are missing.

• Option (4) Trimethyl methanamine — Incorrect. This would describe a methanamine carrying three more methyl groups (four in all), and it also leaves out the N locants.

NCERT (2026-27 edition):
Nomenclature – …