Which of the following halogen compounds cannot be used as a starting material to prepare a primary amine via the Gabriel phthalimide synthesis?

Step-by-step solution

Gabriel phthalimide synthesis involves the nucleophilic substitution ( S_N2 ) of an alkyl halide by the potassium salt of phthalimide (phthalimide anion). Aryl halides, such as chlorobenzene, do not undergo nucleophilic substitution reactions easily under normal conditions. This is due to the partial double bond character of the C-Cl bond arising from resonance, and the sp^2 hybridised state of the carbon atom attached to the halogen. Therefore, the phthalimide anion cannot displace the chloride ion from chlorobenz