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Chlorination of phenol gives para product but bromination of phenol gives Ortho para product why

User Ericpap
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Answer:

here you go

Step-by-step explanation:

The reaction of phenol with bromine is known as bromination of phenol. Solvent has great influence on the reaction. In different solvents, different products are obtained. The action of bromine on phenol can be explained as:

Reaction with bromine in water:—-

Reaction with bromine in water

Phenol reacts with bromine water to give 2,4,6-tribromophenol.

In water, ionisation is facilitated. Phenol gets ionised to form phenoxide ion, which is even better ortho,para-directing. Bromine also gets ionised to a larger extent to form a large number of bromonium ions. And Bromine ions are highly stabilized in ionic solvents. So the formation of strong o,p-directing group and stabilization of Br+ enhances the formation of tribromophenol.

Reaction with bromine in CS2:—-

Reaction with bromine in non-polar organic solvents

Phenol reacts with bromine in a presence of Carbon disulphide to form a mixture of o-bromophenol and p-bromophenol. Among which p-bromophenol predominates. In CS2 ionisation is not facilitated that much. As it is a non-polar solvent it doesn't the Br+ on. Also −OH group is moderately o,p-directing. So as usual para-product is more formed.

User PySaad
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