Method by which Aniline cannot be prepared is:

The method by which aniline cannot be prepared is the method potassium salt of phthalimide treated with chlorobenzene followed by hydrolysis with aqueous NaOH solution.

This is because aryl halides do not undergo nucleophilic substitution with potassium phthalimide under ordinary conditions.

Due to resonance C - Cl bond acquires double bond character.