Question

The order decreasing reactivity towards an electrophilic reagent for the following compound is:
(a) Benzene
(b) Toluene
(c) Chlorobenzene and
(d) Phenol

• A. $d>b>a>c$
• B. $a>b>c>d$
• C. $b>d>a>c$
• D. $d>c>b>a$

Answer 1

Answer: (A)

$d>b>a>c$

Benzene having any activating group i.e $OH,R$ etc under goes electrophilic substitution very easily as compared to benzene itself.

Thus toluene, phenol undergo electrophilic substitution very readily than benzene.

Chlorine with $+E$ and $+M$ effect (delocalized) deactivates the ring due to strong $-I$ effect.So, it is difficult to carry out the substitution in chlorobenzene than in benzene.

Hence, option $A$ is correct.