During debromination of meso-dibromobutane, the major compound formed is
n-butane
but-1-ene
cis-but-2-ene
trans-but-2-ene

Options

A. n-butane
B. but-1-ene
C. cis-but-2-ene
D. trans-but-2-ene

Explanation

To determine the major compound formed during the debromination of meso-dibromobutane, we will follow these steps:

### Step 1: Identify the Structure of Meso-Dibromobutane
Meso-dibromobutane has the following structure:

```
Br
|
CH3-CH-CH-CH3
|
Br
```

This compound has two bromine atoms attached to adjacent carbon atoms.

### Step 2: Understand the Debromination Process
Debromination involves the removal of bromine atoms from the compound. The general reaction can be represented as:

\[ \text{meso-dibromobutane} \rightarrow \text{alkene} + \text{byproducts} \]

In this case, the removal of Br2 leads to the formation of alkenes.

### Step 3: Determine the Possible Products
When the bromine atoms are removed, the following alkenes can be formed:

1. **Cis-but-2-ene**: Both methyl groups (CH3) are on the same side.
2. **Trans-but-2-ene**: The methyl groups are on opposite sides.

### Step 4: Analyze the Stability of the Products
- **Cis-but-2-ene**: This structure has steric hindrance due to the proximity of the two methyl groups, making it less stable.
- **Trans-but-2-ene**: The methyl groups are opposite each other, reducing steric hindrance and making it more stable.

### Step 5: Identify the Major Product
Since trans-but-2-ene is more stable due to less steric hindrance, it will be the major product formed during the debromination of meso-dibromobutane.

### Conclusion
The major compound formed during the debromination of meso-dibromobutane is **trans-but-2-ene**.

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