Question

Why can aromatic primary amines not be prepared by Gabriel phthalimide synthesis?

Answer 1

During Gabriel phthalimide synthesis, the reaction between phthalimide and ethanolic potassium hydroxide gives potassium salt of phthalimide.
The salt on heating with alkyl halide followed by alkaline hydrolysis gives corresponding primary amine.
Aromatic primary amines cannot be prepared by Gabriel phthalimide synthesis as aryl halides do not undergo nucleophilic substitution with the salt formed by phthalimide.