Esters on reaction with EtMgBr give:

Options

A. `1^(@` alcohols
B. `2^(@)` alcohols
C. `3^(@)` alcohols
D. Hydroxy ketone

Explanation

To solve the question regarding the reaction of esters with ethyl magnesium bromide (EtMgBr), we will break down the process step by step.

### Step-by-Step Solution:

1. **Understanding the Reactants**:
- Esters have the general structure RCOOR', where R and R' are alkyl or aryl groups.
- Ethyl magnesium bromide (EtMgBr) is a Grignard reagent, which is an organomagnesium compound. It can be represented as C2H5MgBr.

2. **Mechanism of Reaction**:
- The carbonyl carbon (C=O) in the ester is electrophilic, meaning it is susceptible to attack by nucleophiles.
- The ethyl group (C2H5-) from the Grignard reagent acts as a nucleophile and attacks the carbonyl carbon of the ester.

3. **Formation of the Intermediate**:
- When the ethyl group attacks, the double bond between carbon and oxygen in the carbonyl group breaks, leading to the formation of a tetrahedral intermediate.
- This intermediate can be represented as R-C(OH)(C2H5)-O-MgBr, where the oxygen now carries a negative charge.

4. **Hydrolysis of the Intermediate**:
- Upon hydrolysis (usually by adding water), the intermediate will decompose to form an alcohol and a magnesium salt.
- The final product after hydrolysis will be a tertiary alcohol (R-C(OH)(C2H5)2), where the carbon bearing the hydroxyl group is attached to three different groups (R, C2H5, and C2H5).

5. **Final Products**:
- The reaction of an ester with ethyl magnesium bromide ultimately yields a tertiary alcohol after hydrolysis.

### Summary of the Reaction:
Esters react with ethyl magnesium bromide to form a tertiary alcohol after the nucleophilic attack and subsequent hydrolysis.