Question

What happens when Phenol is treated with bromine water ?

Answer 1

1. When we add bromine water to phenol, it forms 2,4,6-tribromophenol which gives a white precipitate smells like antiseptic.
2. In phenols, mostly electrophilic substitution reaction takes place on the aromatic ring.
3. The $\mathrm{OH}$ group activates the ortho para positions in the ring.
4. Due to resonance effect these positions becomes electron rich.
   
5. This reaction takes place in aqueous solution as phenol forms peroxide ion.
6. This negative ion thus formed makes the ring highly activated and hence a tri substituted product is formed.