Question

The reactivity of compound Z with different halogens under appropriate conditions is given below

The observed pattern of electrophilic substitution can be explain by

• A. the steric effect on the halogen
• B. the steric effect of the tert – butyl group
• C. the electronic effect of the phenolic group
• D. the electronic effect of the tert – butyl group

Answer 1

Answer: (A), (B), (C)

The correct options are
A

the steric effect on the halogen

B

the steric effect of the tert – butyl group

C

the electronic effect of the phenolic group

This problem includes the concept of the effect of steric and electronic effect on the reactivity of organic compounds.
Steric effect of halogens is as follows
$C{l}_2<B{r}_2<I_2$
Electronic effect of phenolic group directs the approaching electrophile towards ortho and para positions.
Tertiary butyl group has a large size so it causes steric effect around the aromatic nucleus. Hence orientation in electrophilic substitution reaction is decided by
(a) The steric effect of halogen
(b) The steric effect of the tertiary butyl group
(c) The electromeric effect of phenolic group