Question

1. Phenyl methenamine
2. N, N - Dimethylaniline
3. N - Methyl aniline
4. Benzenamine

Choose the correct order of the basic nature of the above amines.

Options

• A > C > B > D

• D > B > C > A

• D > C > B > A

• A > B > C > D

Answer 1

A > B > C > D

Explanation:

(A) Phenyl methenamine : pKb = 4.7
(B) N, N - Dimethylaniline : pKb = 8.92
(C) N - Methyl aniline : pKb = 9.3
(D) Benzenamine : pKb = 9.38

(A)> (B) > (C) > (D) 

Alkyl groups donate electrons, increasing the amine's basicity. Because of the delocalization of the lone pair on nitrogen in the ring, aniline has the least fundamental property.