Gabriel phthalimide synthesis is used for the preparation of

primary amine

The correct answer is Option (3) → primary amine

• Gabriel phthalimide synthesis is a method to prepare primary amines.
• The phthalimide anion reacts with an alkyl halide (R–X) to form N-alkyl phthalimide, which upon hydrolysis or hydrazinolysis gives the primary amine (R–NH₂).

OTHER OPTIONS

Option 1: Tertiary amine Gabriel synthesis cannot form tertiary amines because phthalimide has only one reactive nitrogen site.

Option 2: Acid synthesis No carboxylic acid formation occurs.

Option 4: Secondary amine Secondary amines require two alkyl groups on nitrogen, which Gabriel synthesis does not produce.