Methods of Preparation of Phenol
From Cumene (Cumene process)
In this process, benzene is first converted into cumene with propene then oxidized by air to cumene hydroperoide followed by hydrolysis.
From Benzene Diazonium salt
A diazonium salt is formed by treating an aromatic primary amine with nitrous acid at 273-278 K. Diazonium salts are hydrolysed to phenols by warming with water or by treating with dilute acids.
From chlorobenzene (Dow's process): Lab method
Phenol can be prepared by Dow's process which involves the hydrolysis of chlorobenzene with aqueous NaOH at high temperature and pressure followed by treatment with dilute HCl.
