In the given reaction : `C_(2)H_(5)O-overset(O)overset(||)C-(CH_(2))_(3)-CH_(2)-COOC_(2)H_(5)underset((ii)H_(2)O //HCl)overset((i)C_(2)H_(5)ONa//C_(2)H_(5)OH)rarr[X]`
[X] is :

Options

A.
B.
C.
D.

Answer

To solve the given reaction and identify the product [X], we will follow these steps:

### Step 1: Identify the Reactants
The reactants in the given reaction are:
- Diethyl adipate (C2H5O-CO-(CH2)3-COOC2H5)
- Sodium ethoxide (C2H5O-Na)
- Ethanol (C2H5OH)
- Hydrochloric acid (HCl)
- Water (H2O)

### Step 2: Understand the Reaction Mechanism
The reaction involves a condensation reaction known as the **Dieckmann condensation**, which occurs between two ester groups in the diethyl adipate. This reaction leads to the formation of a cyclic beta-ketoester.

### Step 3: Perform the Dieckmann Condensation
1. The sodium ethoxide acts as a base and deprotonates the ethanol, generating an alkoxide ion.
2. This alkoxide ion attacks one of the carbonyl carbons in the diethyl adipate, leading to the formation of a cyclic intermediate.
3. The cyclic intermediate then undergoes intramolecular condensation, resulting in the formation of a beta-ketoester.

### Step 4: Hydrolysis of the Beta-Ketoester
1. The beta-ketoester formed in the previous step is then subjected to hydrolysis in the presence of HCl and water.
2. This hydrolysis converts the beta-ketoester into a beta-keto acid.

### Step 5: Identify the Product [X]
After hydrolysis, the final product [X] is a beta-keto acid. The structure of the beta-keto acid matches with the option provided in the question.

### Final Answer
Thus, the product [X] is the beta-keto acid formed from the hydrolysis of the beta-ketoester.

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