Question

Which compounds have a primary amine?

H2NH2C CH3 NHCH3 H3C NH2 CH3 H2CON-H CH3 -NH2 H E D C A

Answer 1

Amines are derivatives of ammonia, NH₃.

Amines are classified as primary, secondary and tertiary based on the number of carbon atoms directly bonded to the nitrogen atom.

A primary amine has 1 alkyl/ aryl group directly bonded to the nitrogen atom, a secondary amine has 2 alkyl/ aryl groups directly bonded to the nitrogen atom, and a tertiary amine has amine has 3 alkyl/ aryl groups directly bonded to the nitrogen atom.

Therefore, general structure of primary amine would be R-NH₂.

General structure of secondary amine would be R₂-NH.

General structure of tertiary amine would be R₃-N

Where R represents alkyl or aryl groups.

The structures A, B and C are primary amines as they contain 1 alkyl group directly bonded to the nitrogen atom.

D is a secondary amine as it contains 2 alkyl groups bonded to the nitrogen atom.

E is a quarternary ammonium salt as it contains a tetravalent nitrogen atom, with nitrogen carrying a positive charge.