Reactions of benzene diazonium chloride

 Chemical reactions of benzene diazonium chloride

Due to unstable nature diazonium group ( -N₂^- X⁺ ) is a good leaving group. In most of the reactions of diazonium salt, -N₂^-X⁺  group is replaced by other groups. Such reactions are usually grouped under replacement reactions.

In the second type, due to electron deficiency (+ve charge) on diazonium ion, it can behave like an electrophile and couple with electron rich aromatic compounds and undergo coupling reactions.

Replacement reactions of benzene diazonium chloride

Depending on replacing groups these reactions can be mentioned under following heads. In this way we can easily introduce_F, -CI, -I, -OH and -CN groups in the aromatic ring.

1. Replacement by halide ion (Sandmaeyer's reaction)

2. Replacement by cyanide ion

3. Replacement with OH^- ion

4. Replacement with hydrogen

Diazonium salt

Diazonium salt reactions

Diazonium salts have N2 X functional group attached to an aryl group. They are highly unstable and are mainly used as a synthetic intermediate for various compounds. Alkyl diazonium salt do not exist even below 00C.
 
Nomenclature of Diazonium salt
 
The name is obtained by adding diazonium chloride, sulphate etc. to the name of parent hydrocarbon.

Methods of Preparation

Aromatic diazonium salts are prepared from aromatic primary amines. aromatic primary amine is taken in the ice-cold solution of HCL and adding sodium nitrite at 00C we get aromatic diazonium salt. This reaction is known as diazotisation.

Diazonium salt are highly unstable and they are not stored and they are not stored and are used immediately after their preparation.