Ncert Exercises & Solutions

Among the following amines, the strongest Bronsted base is:

1.		2.
3.		4.

Hint:

{sp}^{3}

nitrogen atom is more basic than

{sp}^{2}

nitrogen atom.

Aniline is a weaker base than NH₃ due to the delocalization of the lone pair of electrons of the N-atom over the benzene ring. Pyrrole is also basic than aniline and ammonia because the lone pair of electrons on the N-atom is donated towards aromatic sextet formation.

Therefore, pyrrolidine is the strongest base as lone pair oi nitrogen does not involve in resonance, and also due to the presence of two alkyl ring residue, basic strength becomes high among given four compounds.

Aniline (1): The lone pair on nitrogen is involved in resonance with the benzene ring, reducing its availability to accept a proton, thus decreasing its basicity.
Ammonia (2): It is a neutral amine with a lone pair of electrons on nitrogen, available to accept protons. It has a moderate basicity.
Pyrrole (3): The lone pair on nitrogen is part of the aromaticity of the ring and is not readily available for protonation, making pyrrole a weak base.
Pyrrolidine (4): In pyrrolidine, the lone pair on nitrogen is not involved in resonance, and thus, it is readily available to accept a proton, making it the strongest Brønsted base.

NEET Information

courses

Company

Botany Questions

Chemistry Questions

Physics Questions

Zoology Questions