The reaction between phenol and chloroform in the presence of aqueous NaOH is

Options

A. nucleophilic substitution reaction
B. electrophilic addition reaction
C. electrophilic substitution reaction
D. nucleophilic addition reaction.

Explanation

To solve the question regarding the reaction between phenol and chloroform in the presence of aqueous NaOH, we can follow these steps:

### Step 1: Understand the Reactants
- **Phenol** is an aromatic compound with a hydroxyl (-OH) group attached to a benzene ring.
- **Chloroform (CHCl3)** is a halogenated hydrocarbon that can act as a source of electrophiles in reactions.
- **Aqueous NaOH** provides hydroxide ions (OH-) which can act as a base and facilitate nucleophilic attack.

**Hint:** Identify the functional groups and their reactivity in the reactants.

### Step 2: Identify the Reaction Conditions
- The reaction occurs in the presence of **aqueous NaOH** and typically at elevated temperatures (around 340 K).
- This environment suggests that a nucleophilic substitution reaction may occur, where the nucleophile (OH-) can attack the electrophile (from chloroform).

**Hint:** Consider how the presence of NaOH influences the reactivity of phenol and chloroform.

### Step 3: Mechanism of the Reaction
- The reaction is known as the **Riemer-Tiemann reaction**. In this reaction, phenol reacts with chloroform in the presence of NaOH to form an intermediate.
- The hydroxide ion (OH-) from NaOH attacks the carbon atom of chloroform, leading to the formation of a **chloroformate intermediate**.
- This intermediate can rearrange and undergo hydrolysis to yield **salicylic aldehyde (2-hydroxybenzaldehyde)**.

**Hint:** Look for the formation of intermediates and how they transform into the final product.

### Step 4: Identify the Product
- The final product of the reaction is **salicylic aldehyde**, which is also known as **2-hydroxybenzaldehyde**.
- This product is formed through the electrophilic substitution of the hydroxyl group on phenol with the aldehyde group.

**Hint:** Recognize the significance of the product formed and its relation to the starting materials.

### Step 5: Determine the Type of Reaction
- Since the reaction involves the substitution of a hydrogen atom in phenol with an electrophile (from chloroform), it is classified as an **electrophilic substitution reaction**.
- The presence of the electrophile and the mechanism of substitution confirm this classification.

**Hint:** Classify the reaction based on the nature of the reactants and the mechanism involved.

### Conclusion
The reaction between phenol and chloroform in the presence of aqueous NaOH is an **electrophilic substitution reaction**. Therefore, the correct answer is option C.

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