By a proper choice of reagent, both symmetrical and unsymmetrical ethers can by prepared by williamson synthesis which involves the reaction between an alkyl halide and an alkoxide ion. The reverse process involving the cleavage of etehrs to give back the original alkyl halide and the alcohol can be carried out by heating the ether with HI at 373K.
Q. Allyl phenyl ether can be prepared by heating

Options

A. `C_(6)H_(5)Br+CH_(2)=CH-CH_(2)ON a`
B. `CH_(2)=CHCH_(2)Br+C_(6)H_(5)ON a`
C. `C_(6)H_(5)CH=CHBr+CH_(3)ON a`
D. `CH_(2)+CHB r+C_(6)H_(5)CH_(2)ON a`

Explanation

To prepare allyl phenyl ether through Williamson's synthesis, we need to follow these steps:

### Step 1: Identify the Components
Allyl phenyl ether consists of an allyl group (CH2=CH-CH2) and a phenyl group (C6H5). The ether can be represented as C6H5-O-CH2-CH=CH2.

### Step 2: Choose the Alkyl Halide
For the Williamson synthesis, we need to select an appropriate alkyl halide. In this case, we can use allyl bromide (CH2=CH-CH2Br) as the alkyl halide. This is because allyl bromide is a primary halide, which is suitable for SN2 reactions.

### Step 3: Prepare the Alkoxide Ion
Next, we need to prepare the alkoxide ion. This can be done by deprotonating phenol (C6H5OH) using a strong base such as sodium hydride (NaH) or sodium metal (Na). This will generate phenoxide ion (C6H5O^-).

### Step 4: Carry Out the Williamson Synthesis
Now, we will carry out the Williamson synthesis by reacting the phenoxide ion with allyl bromide. The reaction will proceed via an SN2 mechanism, where the alkoxide ion attacks the carbon atom bonded to the bromine in allyl bromide, resulting in the formation of allyl phenyl ether and the release of bromide ion (Br^-).

The overall reaction can be summarized as follows:
\[ \text{C}_6\text{H}_5\text{O}^- + \text{CH}_2=CH-CH_2\text{Br} \rightarrow \text{C}_6\text{H}_5\text{O-CH}_2\text{CH=CH}_2 + \text{Br}^- \]

### Step 5: Conclusion
Thus, allyl phenyl ether can be successfully prepared by heating phenol with allyl bromide in the presence of a strong base to generate the alkoxide ion.