Amine that cannot be prepared by Gabriel phthalimide synthesis is

Step-by-step solution

Only aliphatic primary amines can be prepared by Gabriel synthesis. Aniline cannot be prepared by this method because aryl halides ( C ₆ H ₅ Cl . or C ₆ H ₅ Br ) do not undergo nucleophilic substitution with potassium phthalimide under ordinary conditions to give N -phenyl phthalimide (i.e., cleavage of C - X bond in haloarenes is quite difficult).