Chapter 23, Problem 23.37P

Interpretation Introduction

Interpretation:

Why bromination of bromobenzene yields more of the para product than chlorination, it is to be explained.

Concept introduction:

The electrophilic aromatic substitution reaction rate increases with an increase in electron density around the ring. The electron donating groups activates whereas the electron withdrawing groups deactivates the aromatic ring. The electron donating groups increases the electron density at ortho-para position and thus they are ortho-para directing. The bulkier atom or groups preferably attached at para-position to reduce the steric strain at ortho position.