Ethyl ester`underset("excess")overset(CH_(3)MgBr)toP`. The product P is

Options

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Explanation

To solve the problem of what product P is when ethyl ester reacts with excess methyl magnesium bromide (CH₃MgBr), we can follow these steps:

### Step 1: Identify the Reactants
We have ethyl ester, which can be represented as CH₃COOC₂H₅ (ethyl acetate), and we are reacting it with excess methyl magnesium bromide (CH₃MgBr).

**Hint:** Remember that esters are generally represented as RCOOR', where R and R' are alkyl groups.

### Step 2: Nucleophilic Addition Reaction
Methyl magnesium bromide (a Grignard reagent) is a strong nucleophile. It will attack the carbonyl carbon of the ethyl ester. The carbonyl carbon is electrophilic due to the partial positive charge, while the oxygen in the carbonyl group has a partial negative charge.

**Hint:** The nucleophile (CH₃⁻) attacks the electrophilic carbon (C=O) in the ester.

### Step 3: Formation of the Intermediate
When the Grignard reagent attacks the carbonyl carbon, it forms a tetrahedral intermediate. The oxygen atom of the ester becomes negatively charged (alkoxide ion), and we have:
\[ \text{CH}_3COO^-C_2H_5 + \text{CH}_3^+ \]

**Hint:** The tetrahedral intermediate is a key step in nucleophilic addition reactions.

### Step 4: Breakdown of the Intermediate
The tetrahedral intermediate can collapse, leading to the formation of a ketone and the release of an alkoxide ion. The alkoxide ion (C₂H₅O⁻) will leave, and we will form acetone (CH₃COCH₃).

**Hint:** The leaving group in this case is the ethoxide ion (C₂H₅O⁻).

### Step 5: Second Nucleophilic Attack
Since we have excess CH₃MgBr, the alkoxide ion formed can undergo another nucleophilic attack by CH₃MgBr. This will lead to the formation of another intermediate.

**Hint:** The presence of excess Grignard reagent allows for further reactions to occur.

### Step 6: Final Product Formation
The final product after hydrolysis will be tert-butyl alcohol (2-methyl-2-propanol). The structure can be represented as:
\[ \text{(CH}_3)_3\text{COH} \]

**Hint:** Hydrolysis is crucial to convert the Grignard product into the corresponding alcohol.

### Conclusion
The product P formed from the reaction of ethyl ester with excess methyl magnesium bromide is tert-butyl alcohol (2-methyl-2-propanol).

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