2-Phenylethanol may be prepared by the reaction of phenyl magnesium bromide with :

Options

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

Answer

To prepare 2-Phenylethanol from phenyl magnesium bromide, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: We start with phenyl magnesium bromide (C6H5MgBr) and need to find a suitable reactant to produce 2-phenylethanol.

2. **Understand the Target Product**: The structure of 2-phenylethanol is:
- It consists of a phenyl group (C6H5) attached to a carbon chain that includes a hydroxyl group (OH) on the second carbon. The structure can be represented as:
```
OH
|
C6H5-C-CH2
```

3. **Use of Ethylene Oxide**: To synthesize 2-phenylethanol, we can use ethylene oxide (an epoxide) as the reactant. Ethylene oxide is a three-membered cyclic ether that can react with Grignard reagents.

4. **Reaction Mechanism**:
- When phenyl magnesium bromide reacts with ethylene oxide, the nucleophilic carbon in the Grignard reagent (C6H5-) attacks the less hindered carbon of the epoxide.
- This results in the opening of the epoxide ring and forms a new carbon-carbon bond.

5. **Formation of the Intermediate**: The reaction proceeds as follows:
- The nucleophilic attack leads to the formation of an alkoxide intermediate:
```
C6H5-MgBr + CH2-CH2-O → C6H5-CH2-CH2-O-MgBr
```

6. **Protonation**: The alkoxide intermediate is then protonated by water (H2O) to yield the final product, 2-phenylethanol:
```
C6H5-CH2-CH2-O-MgBr + H2O → C6H5-CH2-CH2-OH + Mg(OH)Br
```

7. **Final Product**: The final product is 2-phenylethanol (C6H5-CH(OH)-CH3).

### Conclusion:
Thus, the reactant required to prepare 2-phenylethanol from phenyl magnesium bromide is **ethylene oxide**.