The following reaction is known as :
Phenol `overset(1.CHCl_(3)//NaOH) to ` Salicylaldehyde

Options

A. Gattermann aldehyde synthesis
B. Duff reaction
C. Perkin reaction
D. Reimer - Tiemann reaction

Answer

To determine the name of the reaction where phenol is converted to salicylaldehyde using chloroform and sodium hydroxide, we can follow these steps:

### Step 1: Identify the Reactants and Products
- **Reactant**: Phenol (C6H5OH)
- **Product**: Salicylaldehyde (C6H4(OH)CHO)

### Step 2: Recognize the Reagents Used
- The reagents used in the reaction are chloroform (CHCl3) and sodium hydroxide (NaOH).

### Step 3: Understand the Reaction Mechanism
- The reaction involves the formation of a carbene intermediate from chloroform in the presence of a strong base (NaOH). This carbene then reacts with phenol to form salicylaldehyde.

### Step 4: Identify the Type of Reaction
- This reaction is specifically known as the **Riemann-Tiemann reaction**. It is characterized by the conversion of phenol to salicylaldehyde using chloroform and a base.

### Step 5: Eliminate Other Options
- **Gatterman-Aldehyde Synthesis**: Involves the formation of benzaldehyde using HCl and AlCl3.
- **Duff Reaction**: Converts phenol to benzaldehyde using a different reagent.
- **Perkin Reaction**: Involves the reaction of an aldehyde with an acid anhydride in the presence of a base.

### Conclusion
The reaction of phenol to salicylaldehyde using chloroform and NaOH is known as the **Riemann-Tiemann reaction**.

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