Ethers are prepared by the reaction of sodium alkoxides and alkyl halides. Which of the following reagents should be taken to prepare methyl tert-butyl ether ?

Options

A. ` (CH_3)_3 C- Br + NaOCH_3 `
B. `CH_3 Br + Na OC (CH_3)_3 `
C. ` CH_3CH_2Br + NaOC (CH_3)_2 `
D. `(CH_3)_2 C- Br+NaOCH_2CH_3`

Explanation

To prepare methyl tert-butyl ether, we need to follow the Williamson ether synthesis method, which involves the reaction of sodium alkoxide with an alkyl halide. Here’s a step-by-step solution to the question:

### Step-by-Step Solution:

1. **Identify the Required Ether**: We need to prepare methyl tert-butyl ether, which has the structure:
\[ \text{(CH}_3\text{)}_3\text{C-O-CH}_3 \]
This indicates that we need a tert-butyl group (from tert-butyl halide) and a methyl group (from methyl alkoxide).

2. **Determine the Alkoxide**: The alkoxide we require is sodium methoxide (NaOCH₃), which provides the methyl group.

3. **Determine the Alkyl Halide**: The alkyl halide needed is tert-butyl bromide (or tert-butyl chloride), which can be represented as:
\[ \text{(CH}_3\text{)}_3\text{C-Br} \]
This will provide the tert-butyl group.

4. **Reaction Setup**: The reaction will involve sodium methoxide (NaOCH₃) reacting with tert-butyl bromide ((CH₃)₃C-Br). The reaction can be summarized as:
\[ \text{NaOCH}_3 + \text{(CH}_3\text{)}_3\text{C-Br} \rightarrow \text{(CH}_3\text{)}_3\text{C-O-CH}_3 + \text{NaBr} \]

5. **Mechanism**: The reaction proceeds via an SN2 mechanism, where the nucleophile (methoxide ion) attacks the electrophilic carbon in the tert-butyl halide, leading to the formation of the ether and the leaving group (Br⁻).

6. **Conclusion**: Therefore, the correct reagents to prepare methyl tert-butyl ether are sodium methoxide (NaOCH₃) and tert-butyl bromide ((CH₃)₃C-Br).

### Final Answer:
The reagents needed to prepare methyl tert-butyl ether are **sodium methoxide (NaOCH₃)** and **tert-butyl bromide ((CH₃)₃C-Br)**.

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