The basic strength of 1,8-bis(dimethylamino)n | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The correct answer is $(b)$.$1,8-$bis(dimethylamino)naphthalene,also known as a 'proton sponge',exhibits exceptionally high basicity.In $1-$dimeth

Vedclass · Accepted Answer

steric inhibition of resonance

Vedclass · Answer

(B) The correct answer is $(b)$.$1,8-$bis(dimethylamino)naphthalene,also known as a 'proton sponge',exhibits exceptionally high basicity.In $1-$dimethylaminonaphthalene,the lone pair on the nitrogen atom is involved in resonance with the naphthalene ring,which decreases its availability for protonation.In $1,8-$bis(dimethylamino)naphthalene,the two bulky $-N(CH_3)_2$ groups are forced into close proximity at the $1$ and $8$ positions. This causes steric crowding,which forces the lone pairs out of the plane of the naphthalene ring,thereby inhibiting resonance.Since the lone pairs cannot participate in resonance,they are more available for protonation,making the molecule a much stronger base.

The basic strength of $1,8-$bis(dimethylamino)naphthalene is $10^{10}$ times more than $1-$dimethylaminonaphthalene. The reason for this high basic strength is:

Similar Questions

In which of the following does the hyperconjugation effect operate?

Which of the following can show $+M$ or $+R$ effect?

Which type of the overlap of orbitals is involved in hyperconjugation?

Identify the $-I$ effect causing group from the following.

What is the order of $-I$ effect in orbitals?

Vedclass Test Series

Exam Paper Generator

Online Exam Module