From which of the following tertiary butyl alcohol is obtained by the action of methyl magnesium iodide

Options

A. HCHO
B. `CH_(3)`CHO
C. `CH_(3)COCH_(3)`
D. `CO_(2)`

Explanation

To determine from which of the following options tertiary butyl alcohol is obtained by the action of methyl magnesium iodide (CH3MgI), we need to analyze the reaction step by step.

### Step-by-Step Solution:

1. **Understanding Methyl Magnesium Iodide (Grignard Reagent)**:
- Methyl magnesium iodide (CH3MgI) is a Grignard reagent. It acts as a nucleophile and can react with carbonyl compounds (aldehydes and ketones) to form alcohols.

2. **Identifying the Structure of Tertiary Butyl Alcohol**:
- Tertiary butyl alcohol (also known as 2-methyl-2-propanol) has the structure:
```
CH3
|
CH3 - C - OH
|
CH3
```

3. **Analyzing the Given Options**:
- We need to check which option, when reacted with CH3MgI, can lead to the formation of tertiary butyl alcohol. The key is to find a carbonyl compound that can provide the necessary carbon framework.

4. **Option Analysis**:
- **Option A**: HCO (formaldehyde) - This will yield a primary alcohol, not tertiary butyl alcohol.
- **Option B**: CH3CHO (acetaldehyde) - This will yield a secondary alcohol, not tertiary butyl alcohol.
- **Option C**: (CH3)2C=O (acetone) - This is a ketone. When reacted with CH3MgI, it will form a tertiary alcohol.
- **Option D**: Other options (not specified) - Need to check if they can yield tertiary butyl alcohol.

5. **Reaction of Acetone with Methyl Magnesium Iodide**:
- The reaction of acetone with CH3MgI will proceed as follows:
- The nucleophile (CH3-) attacks the carbonyl carbon of acetone.
- This forms a tetrahedral intermediate, which upon hydrolysis will yield tertiary butyl alcohol.
- The reaction can be summarized as:
```
(CH3)2C=O + CH3MgI → (CH3)3C-O-MgI → (CH3)3COH + Mg(OH)I
```

6. **Conclusion**:
- The correct option that gives tertiary butyl alcohol upon reaction with methyl magnesium iodide is **Option C**.

### Final Answer:
**C** (Acetone or (CH3)2C=O is the correct answer).