Chemical properties and uses of Phenols
Electrophilic substitution reactions
The presence of OH group on benzene increases the electron density on the benzene ring making it more susceptible to attack by an electrophile. The reactions involving benzene ring are electrophilic substitution reaction. The presence of OH group makes the orthoand para carbon of benzene more electron rich than meta position. The OH group is called o ‒, p ‒ directing group.
Reactions of phenol involving the cleavage of O–H bond
Esters of phenol gives phenolic ketones on rearrangement in the presence of anhydrous AlCl3. This reaction is called fries rearrangement.
Reaction with dilute HNO3 :
Reaction with conc. HNO3 :
Bromination in solvents of low polarity like CS2 :
The reaction of phenol with bromine water:
Reactions of phenol involving cleavage of the C-O bond
Reaction with zinc dust
Reaction with ammonia:
Uses of phenol
- It is used as an antiseptic.
- It is used as a disinfectant in household cleaners.
- It is used in the preparation of resins, dyes, explosives, lubricants, pesticides, plastics, drugs, etc.