Banzaldehyde can be prepared by oxidation of toluene by

Options

A. Acidic `KMnO_(4)`
B. `K_(2) Cr_(2) O_(7)`
C. `CrO_(2) Cl_(2)`
D. All of these

Answer

To prepare benzaldehyde from toluene through oxidation, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The starting material is toluene, which is also known as methylbenzene (C6H5CH3).

2. **Choose the Oxidizing Agent**:
- To oxidize toluene to benzaldehyde, we need an appropriate oxidizing agent. In this case, chromium chloride (CrO2Cl2) is a suitable choice.

3. **Set Up the Reaction Conditions**:
- The reaction typically takes place in a solvent, which in this case is carbon disulfide (CS2).

4. **Conduct the Reaction**:
- When toluene (C6H5CH3) is treated with chromium chloride (CrO2Cl2) in the presence of carbon disulfide, it undergoes oxidation.

5. **Hydrolysis**:
- After the oxidation step, the product is subjected to hydrolysis. This step converts the intermediate formed during oxidation into benzaldehyde (C6H5CHO).

6. **Final Product**:
- The final product of this reaction is benzaldehyde, which is the desired aldehyde.

### Conclusion:
The oxidation of toluene to benzaldehyde can be achieved using chromium chloride (CrO2Cl2) as the oxidizing agent, followed by hydrolysis.

### Answer:
Benzaldehyde can be prepared by oxidation of toluene using chromium chloride (CrO2Cl2).

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