In the Gabriel's phthalimide synthesis, phthalimide is treated first with `:`

Options

A. `C_(2) H_(5)I//KOH`
B. Ethanolic Na
C. Ethanol and `H_(2)SO_(4)`
D. Ether and `LiAlH_(4)`

Answer

### Step-by-Step Solution:

1. **Understanding Gabriel's Phthalimide Synthesis**:
- Gabriel's phthalimide synthesis is a method used to prepare primary amines from phthalimide. The reaction involves the nucleophilic substitution of a halide by the phthalimide nitrogen.

2. **Identify the Starting Material**:
- The starting material in this synthesis is phthalimide, which has the structure:
\[ \text{C}_6\text{H}_4(\text{CO})_2\text{NH} \]
- This compound consists of a phthalimide ring with two carbonyl groups (C=O) and an amine group (NH).

3. **First Step of the Reaction**:
- The first step involves treating phthalimide with a strong base, typically potassium hydroxide (KOH), in alcoholic conditions. This deprotonates the nitrogen, making it a better nucleophile.

4. **Formation of Phthalimide Anion**:
- The reaction with KOH leads to the formation of the phthalimide anion:
\[ \text{Phthalimide} + \text{KOH} \rightarrow \text{Phthalimide anion} + \text{H}_2\text{O} \]

5. **Nucleophilic Substitution**:
- Next, the phthalimide anion reacts with an alkyl halide, such as ethyl iodide (C2H5I), in a nucleophilic substitution reaction. The iodide ion (I-) is displaced:
\[ \text{Phthalimide anion} + \text{C}_2\text{H}_5\text{I} \rightarrow \text{N-ethylphthalimide} + \text{I}^- \]

6. **Hydrolysis**:
- Finally, the N-ethylphthalimide is hydrolyzed (usually with a strong base like NaOH or KOH) to yield the primary amine (ethylamine) and phthalic acid:
\[ \text{N-ethylphthalimide} + \text{NaOH} \rightarrow \text{C}_2\text{H}_5\text{NH}_2 + \text{Phthalic acid} \]

7. **Conclusion**:
- The correct reagents for the first step in Gabriel's phthalimide synthesis are **C2H5I (ethyl iodide) and KOH**.

### Final Answer:
**C2H5I and KOH**

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