Chemistry - Aromatic Hydrocarbon Question with Solution | TestHub

Key concept

–OH group is strongly activating and ortho/para directing

–CH₃ is also ortho/para directing

Position already occupied → reaction occurs at remaining activated positions

(A) Reaction with Br₂ / H₂O

Phenol reacts very fast → tribromination possible normally

But here one ortho position is blocked by –CH₃⟹

So bromination occurs at:

para position to –OH

remaining ortho position

⟹Product A = 4,6-dibromo-2-methyl phenol

(B) Reaction with Br₂ / CS₂

CS₂ is non-polar → controlled monobromination

Bromine enters para position to –OH (least steric hindrance)

⟹ Product B = 4-bromo-2-methyl phenol