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

Question

The reactivity of compound $Z$ with different halogens under appropriate conditions is given below :\ The observed pattern of electrophilic substitution can be explained by\

Professor PC Thomas Classes · Answer

(a, b, c): $p, q$ and $r$ are suitable positions as per electronic effect of -OH group. Due to steric effect of the tert-butyl group, the bulky electrophiles are less likely to attack positions $q$ and $r$.\ Hence, position $p$ is suitable for $I_{2}$, positions $p$ and $r$ are suitable for $\mathrm{Br}_{2}$ and $\mathrm{Cl}_{2}$ being smaller can attack all $p, q$ and $r$ positions.\