Williamson synthesis of ether is an example of:

Options

A. Nucleophilic addition
B. Electrophilic addition
C. Electrophilic substitution
D. Nucleophilic substitution

Explanation

**Step-by-Step Solution:**

1. **Understanding Williamson Synthesis**: The Williamson synthesis is a method for preparing ethers by the reaction of an alkoxide ion with a primary alkyl halide.

2. **Identifying the Reactants**: In this reaction, we typically use sodium alkoxide (R-O⁻Na⁺) as the nucleophile and a primary alkyl halide (R'-X, where X is a halogen like Br or Cl).

3. **Mechanism of Reaction**:
- The alkoxide ion (R-O⁻) acts as a nucleophile, which means it is an electron-rich species.
- The alkyl halide (R'-X) is an electrophile, where the carbon atom attached to the halogen is electron-deficient due to the electronegativity of the halogen.

4. **Nucleophilic Attack**: The alkoxide ion attacks the carbon atom of the alkyl halide, leading to the formation of a new bond between the oxygen of the alkoxide and the carbon of the alkyl halide.

5. **Leaving Group Departure**: As the alkoxide attacks, the halogen (X) leaves as a halide ion (X⁻), which is a stable leaving group. This results in the formation of the ether (R-O-R').

6. **Conclusion**: The overall reaction can be summarized as:
\[ R-O⁻ + R'-X \rightarrow R-O-R' + X⁻ \]
This shows that the Williamson synthesis of ether is a nucleophilic substitution reaction, where the nucleophile (alkoxide) substitutes the leaving group (halide) in the alkyl halide.

**Final Answer**: Williamson synthesis of ether is an example of a **nucleophilic substitution reaction**.

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