Question

Which of the following compound is the strongest base?

• A.
• B.
• C.
• D.

Answer 1

The correct option is B

Comparing the basic character of the given compounds

The basic character of amines is due to the presence of lone pair of electrons. When lone pair on the nitrogen atom is conjugated, the electron density on nitrogen becomes less due to delocalisation of the lone pair. So, the basic strength decreases.

(A)

In this option, the lone pair of electrons on nitrogen atom is not delocalised.

(B)

Lone pair of electrons on nitrogen atom is in conjugation with both benzene ring and carbonyl group.

(C)

Lone pair of electrons on the nitrogen atom is in conjugation with the benzene ring.
(D)

Lone pair of electrons on nitrogen atom is in conjugation with the carbonyl group. So, option (B), (C) and (D) will be weaker base than (A).

Therefore, the correct answer is option (A).