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 compound is most easily hydrolyzed with aqueous KOH solution, we need to analyze the stability of the carbocations formed during the hydrolysis process. The stability of carbocations is influenced by several factors, including resonance, hyperconjugation, and inductive effects.

### Step-by-Step Solution:

1. **Identify the Compounds**: Let's assume we have four different compounds that can undergo hydrolysis with KOH. For example, we can consider:
- Compound 1: CH3Cl (methyl chloride)
- Compound 2: C6H5CH2Cl (benzyl chloride)
- Compound 3: CH2=CHCl (vinyl chloride)
- Compound 4: C6H5CHClCH3 (allyl chloride)

2. **Understand Hydrolysis Mechanism**: When KOH is added, the chloride ion (Cl-) leaves, forming a carbocation. The hydroxide ion (OH-) then attacks this carbocation to form the corresponding alcohol.

3. **Form the Carbocations**:
- For CH3Cl, the carbocation formed is CH3+ (methyl carbocation).
- For C6H5CH2Cl, the carbocation formed is C6H5CH2+ (benzyl carbocation).
- For CH2=CHCl, the carbocation formed is CH2=CH+ (vinyl carbocation).
- For C6H5CHClCH3, the carbocation formed is C6H5C+HCH3 (allylic carbocation).

4. **Evaluate Carbocation Stability**:
- **Methyl Carbocation (CH3+)**: This is a primary carbocation and is very unstable due to lack of stabilization factors.
- **Benzyl Carbocation (C6H5CH2+)**: This carbocation is stabilized by resonance from the benzene ring, making it relatively stable.
- **Vinyl Carbocation (CH2=CH+)**: This is also a primary carbocation and is less stable due to lack of resonance or hyperconjugation.
- **Allylic Carbocation (C6H5C+HCH3)**: This carbocation is stabilized by resonance and hyperconjugation, making it more stable than the others.

5. **Conclusion**: The stability of the carbocations indicates that the benzyl carbocation (from C6H5CH2Cl) and the allylic carbocation (from C6H5CHClCH3) are the most stable. However, the allylic carbocation is more stable due to additional stabilization factors. Therefore, the compound that is most easily hydrolyzed with aqueous KOH is the one that forms the most stable carbocation.

### Final Answer:
The compound that is most easily hydrolyzed with aqueous KOH solution is **C6H5CHClCH3 (allyl chloride)**.