Reagent used to convert allyl alcohol to acrolein is :

Options

A. `MnO_(2)`
B. `KMnO_(4)`
C. `O_(s)O_(4)`
D. `H_(2)O_(2)`

Answer

To convert allyl alcohol to acrolein, we need to follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The starting compound is allyl alcohol, which has the structure CH2=CH-CH2OH.

2. **Identify the Product**:
- The desired product is acrolein, which has the structure CH2=CH-CHO.

3. **Understand the Reaction Type**:
- The conversion involves oxidation of the alcohol functional group (-OH) to an aldehyde (-CHO).

4. **Select the Appropriate Reagent**:
- The reagent that can facilitate this oxidation without affecting the double bond is manganese dioxide (MnO2).

5. **Reaction Conditions**:
- The reaction is typically carried out in the presence of an inert solvent such as dichloromethane (CH2Cl2) or carbon tetrachloride (CCl4) to maintain mild and neutral conditions.

6. **Mechanism of the Reaction**:
- MnO2 selectively oxidizes the allylic alcohol to the corresponding aldehyde (acrolein) without attacking the double bond.

7. **Conclusion**:
- Therefore, the reagent used to convert allyl alcohol to acrolein is manganese dioxide (MnO2).

### Final Answer:
The reagent used to convert allyl alcohol to acrolein is **MnO2 (manganese dioxide)**.

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