Which of the following alcohol can not be prepared by the reaction of acid chloride with excess of Grignard reagent by acidification ?

Options

A.
B.
C.
D.

Explanation

To determine which alcohol cannot be prepared by the reaction of acid chloride with excess Grignard reagent followed by acidification, we need to understand the mechanism of the reaction and the requirements for the formation of the alcohol.

### Step-by-Step Solution:

1. **Understanding the Reaction**:
- Acid chlorides (RCOCl) react with Grignard reagents (R'MgX) to form tertiary alcohols after hydrolysis. The general reaction can be represented as:
\[ RCOCl + R'MgX \rightarrow RCO(R')MgX \rightarrow R(OH)(R') + HCl \]
- Here, R and R' can be the same or different alkyl groups.

2. **Formation of Tertiary Alcohols**:
- When an acid chloride reacts with a Grignard reagent, the carbonyl carbon of the acid chloride is attacked by the nucleophilic Grignard reagent, leading to the formation of a tetrahedral intermediate. This intermediate can then undergo hydrolysis to yield an alcohol.

3. **Analyzing the Options**:
- We need to analyze the given options to see which alcohol cannot be formed based on the requirement that two alkyl groups (R and R') must be the same, while one can be different.
- Let's denote the options as follows:
1. Option A: R = Ph, R' = Ph
2. Option B: R = Ph, R' = Alkyl
3. Option C: R = Alkyl, R' = Alkyl
4. Option D: R = Alkyl, R' = Different Alkyls

4. **Identifying the Correct Option**:
- **Option A**: Both groups are the same (Ph, Ph). This can be formed.
- **Option B**: One group is Ph, and the other is an alkyl. This can be formed.
- **Option C**: Both groups are alkyl (same). This can be formed.
- **Option D**: All groups are different (e.g., Ethyl, Methyl, Ph). This cannot be formed because the requirement for the reaction is that two of the groups must be the same.

5. **Conclusion**:
- Therefore, the alcohol that cannot be prepared by the reaction of acid chloride with excess Grignard reagent followed by acidification is **Option D**.

### Final Answer:
**Option D** cannot be prepared by the reaction of acid chloride with excess Grignard reagent followed by acidification.