Explain why phenol with bromine water forms 2,4,6-tribromophenol while on reaction with bromine in `CS_(2)` at low temperature forms para-bromophenol as the major product .

Explanation

a) Phenol undergoes Bromination in presence of `CS_(2)` to form p-bromophenol as major product

b) Phenol undergoes bromination in aqueous medium form 2,4,6-tribrome phenol (white ppt).

Explain : In bromination of phenol, the polarisation of `Br_(2)` molecule takes place even in the absence of Lewis acid. This is due to be highly activating effect of -OH group attached to teh benzene ring.