Aromatic Halogen Compounds

Aromatic Halogen Compounds:- Benzene and its homologues react with halogens to produce either addition or substitution products.

i)            Addition compounds:- These compounds are obtained by exposing the mixture of aromatic hydrocarbon and the halogen to direct sunlight, e.g., benzene hexachloride benzene hexabromide, etc.

ii)          Substitution products:- Two types of halogen substituted products are known.

a)  Nuclear Halogen substitution products:- In these products, the halogen is linked directly to the carbon of the benzene nucleus. These products are generally called aryl halides.

b)  Side chain halogen substitution products:- In these products, the halogen is linked to the carbon atom of the side chain. These are also called side chain aryl halides. They have properties similar to alkyl halides.

Aryl halides:- According to IUPAC system, aryl halides are named as Haloarenes. If more than one halogen is present, their positions in the ring are indicated by numbers or appropriate prefixes, ortho, meta, para.