The correct order of base strength of the following amines is

see full answer

Your Exam Success, Personally Taken Care Of

1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.

An Intiative by Sri Chaitanya

o – nitroaniline > m – nitroaniline > p – nitroaniline

m – nitroaniline > p – nitroaniline > o – nitroaniline

m – nitroaniline > o – nitroaniline > p – nitroaniline

o – nitroaniline > p – nitroaniline > m – nitroaniline

answer is B.

(Unlock A.I Detailed Solution for FREE)

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

The pKa values of m - nitroaniline, p - nitroaniline and o - nitroaniline isomers are 2.5, 1.0 and -0.3 respectively.
Due to the presence of the electron-withdrawing nitro group, the delocalization of the lone pair of electron is improved.
This effect is observed in para and ortho position.
In the ortho position, a very close inductive effect of the nitro group is also observed. (ortho effect)
Hence, o - nitroaniline is less basic than p - nitroaniline.
In m - nitroaniline, only the inductive effect is present.
The decreasing order of basicity is m - nitroaniline > p - nitroaniline > o - nitroaniline.

Watch 3-min video & get full concept clarity