Which of the following is most easily hydrolysed with aqueous KOH solution ?

Options

A. `CH_3Cl`
B. `C_6H_5CH_2Cl`
C. `CH_2=CHCl`
D. `C_6H_5-underset(Cl)underset(|)(CH)-CH_3`

Answer

To determine which of the given compounds is most easily hydrolyzed with aqueous KOH solution, we need to analyze the stability of the carbocations formed during the hydrolysis process.

### Step-by-Step Solution:

1. **Understanding Hydrolysis with KOH**:
Hydrolysis of alkyl halides involves the substitution of the halide ion (like Cl, Br, etc.) with hydroxide ion (OH⁻) from KOH. This process often leads to the formation of a carbocation intermediate.

2. **Formation of Carbocations**:
When an alkyl halide undergoes hydrolysis, the halide ion leaves, forming a carbocation. The stability of this carbocation is crucial because more stable carbocations will lead to faster hydrolysis.

3. **Evaluating Carbocation Stability**:
The stability of carbocations can be ranked as follows:
- Tertiary carbocations (3°) > Secondary carbocations (2°) > Primary carbocations (1°) > Methyl carbocations (CH₃⁺).
- Additionally, resonance stabilization can significantly enhance carbocation stability.

4. **Analyzing Given Compounds**:
Let's assume we have four different alkyl halides to consider:
- Compound A: CH₃Cl (Methyl chloride)
- Compound B: CH₂=CHCl (Vinyl chloride)
- Compound C: C₆H₅CH₂Cl (Benzyl chloride)
- Compound D: C₆H₅CHCl (Allyl chloride)

Now, we analyze the carbocations formed from each compound:
- **Compound A**: Forms a methyl carbocation (CH₃⁺) which is very unstable.
- **Compound B**: Forms a vinyl carbocation (CH₂=CH⁺) which is also unstable due to lack of stability from resonance.
- **Compound C**: Forms a benzyl carbocation (C₆H₅CH₂⁺) which is stabilized by resonance from the benzene ring.
- **Compound D**: Forms an allyl carbocation (C₆H₅CH⁺) which is also stabilized by resonance but less than benzyl.

5. **Conclusion**:
Among the compounds analyzed, **Compound C (Benzyl chloride)** forms the most stable carbocation due to resonance stabilization from the adjacent benzene ring. Therefore, it will be hydrolyzed most easily in aqueous KOH solution.

### Final Answer:
**Benzyl chloride (C₆H₅CH₂Cl) is most easily hydrolyzed with aqueous KOH solution.**