One mole of alkene on ozonolysis gives of butanone. The alkene is

Options

A. 3,4-dimethylhex-2-ene
B. 2,3-dimethylhex-3-ene
C. 3,4-dimethylhex-3-ene
D. 2,3-dimethylhex-2-ene

Explanation

To determine the alkene that gives butanone upon ozonolysis, we can follow these steps:

### Step 1: Understand Ozonolysis
Ozonolysis is a reaction where alkenes react with ozone (O₃) to form carbonyl compounds (aldehydes or ketones). The double bond in the alkene is cleaved, and each carbon atom involved in the double bond is oxidized to form a carbonyl group.

### Step 2: Identify the Product
The question states that one mole of alkene gives butanone upon ozonolysis. Butanone (C₄H₈O) is a ketone with the structure:

```
O
||
CH₃-C-CH₂-CH₃
```

### Step 3: Determine the Structure of the Alkene
To find the alkene that yields butanone, we need to consider how the ozonolysis would break the double bond and lead to the formation of butanone.

1. **Butanone has 4 carbon atoms**. Therefore, the alkene must have at least 4 or more carbon atoms.
2. **The ozonolysis of the alkene should yield butanone**. This means that when the double bond is cleaved, one of the products must be butanone.

### Step 4: Possible Alkene Structures
Let’s consider a few possible alkenes:

1. **2-Butene (C₄H₈)**:
- Structure: CH₃-CH=CH-CH₃
- Ozonolysis would yield two molecules of butanone.

2. **1-Pentene (C₅H₁₀)**:
- Structure: CH₂=CH-CH₂-CH₂-CH₃
- Ozonolysis would yield butanone and an aldehyde.

3. **3-Hexene (C₆H₁₂)**:
- Structure: CH₃-CH₂-CH=CH-CH₂-CH₃
- Ozonolysis would yield butanone and another carbonyl compound.

### Step 5: Conclusion
The alkene that gives butanone upon ozonolysis is **2-Butene**. When 2-butene undergoes ozonolysis, it breaks down to form two molecules of butanone.

### Final Answer
The alkene is **2-butene**.

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