Question

Rank in order of increasing rate of reaction towards EAS with bromine in the presence of $FeB{r}_3$.

• A. $B<A<C$
• B. $B<C<A$
• C. $A<B<C$
• D. $A<C<B$

Answer 1

The correct option is A $B<A<C$

For bromination on benzene ring or for electrophilic aromatic substitution, an electron donating group should be attached to the ring.

In case of C (Refer to Image 1)

$⟶$ Oxygen donate its electron to the ring and make it more activation.

$⟶$ Only electron donating group attached.

In case of A (Refer to Image 2)

$⟶$ Both electron donating and electron withdrawing group are present which make the ring less activating than C.

In case of B (Refer to Image 3)

$⟶$ As only electron withdrawing group is attached to the ring which makes the ring more deactivating towards Electrophilic substitution.

Thus the order for EAS is $C>A>B$ .