Oxidation of But-2-yne with alkaline `KMnO_4` gives :

Answer

To solve the question regarding the oxidation of But-2-yne with alkaline KMnO4, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure of But-2-yne**:
- But-2-yne is an alkyne with the molecular formula C4H6. Its structure can be represented as:
\[ \text{CH}_3 - \text{C} \equiv \text{C} - \text{CH}_3 \]
- This indicates that there is a triple bond between the second and third carbon atoms.

2. **Understand the Role of KMnO4**:
- Potassium permanganate (KMnO4) is a strong oxidizing agent, especially in alkaline conditions. It is known for its ability to oxidize alkynes to form carbonyl compounds.

3. **Oxidation Reaction**:
- When But-2-yne is treated with alkaline KMnO4, the triple bond undergoes oxidation. The reaction leads to the formation of a diketone.
- The oxidation process involves the addition of oxygen across the triple bond, resulting in the formation of two carbonyl (C=O) groups.

4. **Product Formation**:
- The product formed from the oxidation of But-2-yne is Butane-2,3-dione. The structure of Butane-2,3-dione can be represented as:
\[ \text{CH}_3 - \text{C}(=O) - \text{C}(=O) - \text{CH}_3 \]
- This compound has two ketone functional groups located at the second and third carbon atoms.

5. **Final Answer**:
- Therefore, the oxidation of But-2-yne with alkaline KMnO4 gives Butane-2,3-dione.

### Summary:
The final product of the oxidation of But-2-yne with alkaline KMnO4 is **Butane-2,3-dione**.

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