The reaction,
`RX-R'-ONatoR'-O-R+NaX` is called

Options

A. Wurtz reaction
B. Williamson's synthesis
C. Kolbe's reaction
D. Hofmann bromamide reaction.

Explanation

To solve the question regarding the reaction `RX-R'-ONa -> R'-O-R + NaX`, we need to identify what this reaction is called. Here’s a step-by-step breakdown:

### Step 1: Identify the Reactants
The reactants in the given reaction are:
- `RX`: An alkyl halide
- `R'-O-Na`: Sodium alkoxide

### Step 2: Understand the Reaction Mechanism
In this reaction, the alkoxide ion (which is a strong nucleophile) attacks the alkyl halide. The nucleophile (alkoxide) replaces the halide ion (X) in the alkyl halide.

### Step 3: Write the Products
The products of this reaction are:
- An ether (`R'-O-R`)
- Sodium halide (`NaX`)

### Step 4: Name the Reaction
This reaction is known for forming ethers from alkyl halides and alkoxides. The specific name for this reaction is **Williamson Ether Synthesis**.

### Step 5: Verify the Options
From the options provided:
1. Woods reaction
2. Williamson synthesis
3. Coles reaction
4. Hoffman Bromamide reaction

The correct answer is **Williamson synthesis**, which corresponds to the mechanism we just discussed.

### Final Answer
The reaction `RX-R'-ONa -> R'-O-R + NaX` is called **Williamson Ether Synthesis**.

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