In the given reaction `CH_(3)CH_(2) CH -= CHCH_(3) overset(X) to CH_(3)CH_(2)COOH + CH_(3)COOH`
The X is

Options

A. `C_(2)H_(5)ON a`
B. Conc. `HCl + "Anhy"ZnCl_(2)`
C. Anh. `AlCl_(3)`
D. `KMnO_(4)//OH^(-)`

Explanation

To solve the given reaction:

**Reaction:**
\[ \text{CH}_3\text{CH}_2\text{CH}=\text{CHCH}_3 \xrightarrow{X} \text{CH}_3\text{CH}_2\text{COOH} + \text{CH}_3\text{COOH} \]

1. **Identify the reactant:** The reactant is 1-pentene (CH₃CH₂CH=CHCH₃), which is a 5-carbon alkene with a double bond between the second and third carbon atoms.

2. **Understand the products:** The products are propanoic acid (CH₃CH₂COOH) and acetic acid (CH₃COOH). This indicates that the double bond in the alkene is being cleaved and converted into two carboxylic acids.

3. **Determine the type of reaction:** The reaction involves oxidative cleavage of the alkene, which means that the double bond will break and two carbonyl groups will be formed, which will then be further oxidized to carboxylic acids.

4. **Identify the reagent (X):** We need to find a reagent that can perform oxidative cleavage. Common reagents for this purpose include potassium permanganate (KMnO₄) in a basic medium or ozone (O₃).

5. **Evaluate the options:**
- **Option 1:** Sodium methoxide - This is a base, not an oxidizing agent.
- **Option 2:** Concentrated HCl with anhydrous zinc chloride (Lucas reagent) - This is used for alcohols, not for cleaving alkenes.
- **Option 3:** Anhydrous aluminum trichloride - This is a Lewis acid, not an oxidizing agent.
- **Option 4:** Potassium permanganate in basic medium - This is a strong oxidizing agent and is capable of performing oxidative cleavage of alkenes.

6. **Conclusion:** The correct reagent (X) that facilitates the oxidative cleavage of 1-pentene to yield propanoic acid and acetic acid is potassium permanganate in basic medium.

**Final Answer:**
\[ X = \text{Potassium permanganate (KMnO}_4\text{) in basic medium} \]

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