Gabriel phthalimide synthesis is a method used for the preparation of primary amines. It involves the conversion of phthalimide, a cyclic imide, into an amine by reaction with an alkyl halide. This reaction is an example of nucleophilic substitution reaction.

Here is a detailed explanation of the Gabriel phthalimide synthesis and its use in the preparation of primary amines:

1. Gabriel Phthalimide Synthesis:
The Gabriel phthalimide synthesis is named after its inventor, Siegmund Gabriel. It is a common method for the synthesis of primary amines. The reaction involves three steps:

a) Activation of phthalimide: Phthalimide is first converted into its sodium salt by treatment with sodium hydroxide or sodium ethoxide. This step makes the nitrogen atom of the phthalimide more nucleophilic.

b) Reaction with alkyl halide: The activated phthalimide reacts with an alkyl halide (such as an alkyl bromide or alkyl iodide) in the presence of a strong base, usually potassium carbonate (K₂CO₃). The base facilitates the deprotonation of the alkyl halide and the nucleophilic attack of the phthalimide nitrogen on the carbon atom of the alkyl halide.

c) Hydrolysis: The product obtained from the reaction is a phthalimide derivative containing the desired amine functionality. This phthalimide derivative is then hydrolyzed using a strong base, such as sodium hydroxide (NaOH) or potassium hydroxide (KOH), to give the corresponding primary amine.

2. Preparation of Primary Amines:
Using the Gabriel phthalimide synthesis, primary amines can be prepared by reacting phthalimide with an alkyl halide. The alkyl group in the alkyl halide determines the nature of the primary amine obtained. By varying the alkyl halide used, different primary amines can be synthesized.

In the given question, the correct answer is option 'D', which states that the Gabriel phthalimide synthesis is used in the preparation of 10 amines. This means that the synthesis can be used to prepare 10 different primary amines by varying the alkyl halide used.

Overall, the Gabriel phthalimide synthesis is a versatile method for the preparation of primary amines, allowing for the synthesis of a wide range of compounds with different alkyl groups.