`CH_(3)-underset(CH_(3))underset(|)(CH)-underset(Br)underset(|)(CH)-CH_(3)("SN"^(1)//C_(2)H_(5)"ONa")/("Williamson Reaction")`Ether is -

Options

A. `CH_(3)-underset(CH_(3))underset(|)overset(OC_(2)H_(5))overset(|)C-CH_(2)-CH_(3)`
B. `CH_(3)-underset(CH_(3))underset(|)(CH)-underset(OC_(2)H_(5))underset(|)(CH)-CH_(3)`
C. Both correct
D. None is correct

Answer

To solve the problem, we need to determine the ether that is formed from the given reactant through the Williamson reaction, which proceeds via an SN1 mechanism. Let's break down the steps:

### Step 1: Identify the Reactant
The reactant is given as:
\[ \text{CH}_3 - \text{C}(\text{Br}) - \text{C}(\text{CH}_3) - \text{CH}_3 \]
This can be represented as a 2-bromo-3-methylbutane.

### Step 2: Mechanism of SN1 Reaction
In an SN1 reaction, the first step involves the formation of a carbocation. The bromine (Br) atom will leave, resulting in the formation of a carbocation.

### Step 3: Carbocation Formation
When Br leaves, the structure becomes:
\[ \text{CH}_3 - \text{C}^+ - \text{C}(\text{CH}_3) - \text{CH}_3 \]
This is a secondary carbocation.

### Step 4: Carbocation Rearrangement
To stabilize the carbocation, a hydride shift can occur. A hydrogen atom from the adjacent carbon can shift to the positively charged carbon, forming a more stable tertiary carbocation:
\[ \text{CH}_3 - \text{C}(\text{CH}_3) - \text{C}^+ - \text{CH}_3 \]
After the hydride shift, the structure becomes:
\[ \text{CH}_3 - \text{C}^+ - \text{C}(\text{CH}_3) - \text{CH}_3 \]
This tertiary carbocation is more stable than the secondary one.

### Step 5: Nucleophile Attack
The nucleophile in this reaction is sodium ethoxide (\( \text{C}_2\text{H}_5\text{O}^- \)). The negatively charged oxygen will attack the carbocation:
\[ \text{CH}_3 - \text{C}^+ - \text{C}(\text{CH}_3) - \text{CH}_3 + \text{C}_2\text{H}_5\text{O}^- \rightarrow \text{CH}_3 - \text{C}(\text{C}_2\text{H}_5\text{O}) - \text{C}(\text{CH}_3) - \text{CH}_3 \]

### Step 6: Formation of Ether
The final product is an ether, which can be represented as:
\[ \text{CH}_3 - \text{C}(\text{C}_2\text{H}_5\text{O}) - \text{C}(\text{CH}_3) - \text{CH}_3 \]
This ether is known as ethyl-2-methylpropyl ether.

### Conclusion
The ether formed from the reaction is ethyl-2-methylpropyl ether.