Question

Some meta-directing substituents in aromatic substitution
are given. Which one is most deactivating? [2013]
(a) –SO₃H (b) –COOH
(c) –NO₂ (d) –C º N

Answer 1

Answer:

(c) –NO₂ (d) –C º N is answer

...plsss mark as brainlist answer.....

Answer 2

• One which is most deactivating is –NO₂

• It is due to the fact that –NO₂ shows both - I and - M effect

• -I effect : Electron withdrawing substituents tend to attract electron pair from adjacent carbon due to which it carries positive charge. This effect is called as negative inductive effect and the groups which cause this effect are called as -I groups.

• -M effect : The mesomeric effect is negative (–M) when the substituent is an electron-withdrawing group