Chemistry 3 Marks Question

Gabriel phthalimide synthesis : This is best method of the preparation of aliphatic amine. In this method phthalimide is treated with ethanolic potassium hydroxide forms potassium sort of phthalimide which on heating with alkyl halide followed by alkaline hydrolysis produces the corresponding primary amine aromatic primary amines like aniline can not be prepared easily by this method because the reactivity of aryl halides is less than alkyl halides.

Coupling Reaction : Benzene diazonium chloride reacts with phenol in which the phenol molecule at its pure position is coupled with the diazonium salt to form p-hydroxyazobenzene. This type of reaction is known as coupling reaction. Similarly the reaction of diazonium salt with aniline yields p-aminoazobenzene. This is an example if electrophilic substitution reaction products obtained are coloured and these are azo dyes.