Benzene on ozonolysis yields

Options

A. Glyoxal
B. Acetone
C. Propanol
D. Butanone

Answer

To solve the question regarding the ozonolysis of benzene, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Ozonolysis**: Ozonolysis is a reaction where ozone (O₃) reacts with alkenes or alkynes to cleave double bonds and form carbonyl compounds. In the case of benzene, which has alternating double bonds, ozonolysis will cleave these double bonds.

2. **Structure of Benzene**: Benzene (C₆H₆) has a hexagonal structure with alternating double bonds. It can be represented as:
```
C
/ \
C C
|| ||
C---C
\ /
C
```

3. **Reaction with Ozone**: When benzene undergoes ozonolysis, the ozone molecule will react with the double bonds. Each double bond will be cleaved, and an oxygen atom will be added to each of the carbons that were involved in the double bond.

4. **Formation of Glyoxal**: The ozonolysis of benzene leads to the formation of glyoxal (C₂H₂O₂). This occurs because the cleavage of the three double bonds in benzene results in the formation of three carbonyl groups (C=O) on the adjacent carbon atoms, leading to the structure:
```
O=C-C=O
```

5. **Final Products**: The ozonolysis of benzene yields glyoxal as the main product. In addition, depending on the reaction conditions and further reductions, other products like acetone, propanol, and butanol can also be formed, but glyoxal is the primary product from the ozonolysis of benzene.

### Conclusion:
Thus, the ozonolysis of benzene primarily yields **glyoxal**.

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