The most effective pair of reagents for the preparation of tert bytyl ethyl ehter is :

Options

A. potassium tert-bytoxide and ethyl bromide
B. potassium tert-butoxide and ethanol
C. sodium ethxoide and tert-butyl bromide.
D. tert-butyl alcohol and ethyl bromide.

Explanation

To prepare tert-butyl ethyl ether, we can use the Williamson synthesis method. This method involves the reaction of an alkoxide with a primary alkyl halide. Here’s a step-by-step solution:

### Step 1: Identify the Required Ether
We need to prepare tert-butyl ethyl ether. The structure of tert-butyl ethyl ether can be represented as:
- tert-butyl group: (CH₃)₃C-
- ethyl group: CH₃CH₂-

### Step 2: Choose the Alkoxide
To create tert-butyl ethyl ether, we need to form an alkoxide from tert-butyl alcohol (tert-butanol). The alkoxide ion is formed by deprotonating tert-butanol:
- tert-butanol (C₄H₁₀O) reacts with a strong base (like sodium hydride or sodium metal) to form tert-butoxide (C₄H₉O⁻).

### Step 3: Choose the Alkyl Halide
Next, we need an alkyl halide to react with the alkoxide. For the ethyl part of the ether, we can use ethyl bromide (C₂H₅Br) as the alkyl halide.

### Step 4: Perform the Reaction
The reaction involves the nucleophilic attack of the tert-butoxide ion on the ethyl bromide:
- tert-butoxide (C₄H₉O⁻) attacks the ethyl bromide (C₂H₅Br) via an SN2 mechanism, leading to the formation of tert-butyl ethyl ether (C₄H₉OC₂H₅) and the release of bromide ion (Br⁻).

### Step 5: Write the Overall Reaction
The overall reaction can be summarized as:
\[ \text{C₄H₉OH (tert-butanol) + Na → C₄H₉O⁻ (tert-butoxide) + NaBr} \]
\[ \text{C₄H₉O⁻ + C₂H₅Br → C₄H₉OC₂H₅ (tert-butyl ethyl ether) + Br⁻} \]

### Conclusion
Thus, the most effective pair of reagents for the preparation of tert-butyl ethyl ether is:
- **tert-butyl alcohol (C₄H₉OH)** and **ethyl bromide (C₂H₅Br)**.