Table of Contents
Method of preparation of phenol
There are some important methods for preparation of phenol
1. From benzene sulphuric acid
First of all, benzene sulphonic is react with sulphuric acid(H2SO4). When sodium salts of aromatic sulphonic acid are fused with sodium hydroxide, sodium derivatives of phenol are obtained which is acidification yield phenol.
2. Dow’s process
When chlorobenzene is heated with excess of aqueous NaOH at 623K and 300atm it formed sodium phenoxide, which further hydrolyzed by dilute HCl, it formed phenol.
3. From Cumene(Cumene process)
Cumene is oxidized using air to give Cumene hydro phenoxide, which on acidification yield phenol.
4. From benzene diazonium salt
When benzene diazonium chloride is heated with water, it produces phenol with liberation at N2 gas.
Physical properties of phenol
There are some important physical properties of phenol:
1. It is a colorless or crystalline solid
2. It has a melting point of 41°C
3. It has a boiling point of 182°C
4. It is soluble in water
5. It is used in disinfectant
Chemical reactions of phenol
Phenol are reactive in nature and can undergoes both electrophilic and nucleophilic substitution reactions. There are some chemical reactions of phenol:
1. Formation of salt
When phenol is reacted with sodium hydroxide then sodium phenoxide and water formed.
2. Electrophilic substitution reaction
Phenol is react with dilute HNO3 to give a mixture of O-nitrophenol and P-nitrophenol
3. Kolbe’s reaction
Phenol react with sodium hydroxide to form sodium phenoxide, which react with carbon dioxide to form salicylic acid
4. Reduction reaction
When phenol is distilled with zinc dust, low yield is obtained.
Structure and uses of phenol, cresol, resorcinol and naphthol’s
Structure and uses of phenol
1. It is used as raw material for drug
2. It is used in preservatives, antiseptic etc.
3. It is used as a starting material like aspirin.
4. It is used for dyes like phenolphthalein.
Structure and uses of cresol
1. They are strong germicides used in disinfectants
2. It is also used in wood preservatives.
3. M-cresol is used in making photographic developer.
4. O-cresol is used as a solvent, disinfectant and chemical intermediate.
Structure and uses of resorcinol
1. It is used in manufacturing of resins.
2. It is also used as a disinfectant or an antiseptic in pharmaceutical products.
3. It is used in the treatment of gastric ulcer.
4. It is used as a skin protectant.
Structure and uses of naphthol’s
1. It is used as insecticides
2. It is also used in making of dyes
3. It is also used in perfumery.
preparation of phenol