Which of the following reactions does not form salicylic acid ?

Options

A. Permanganate oxidarion of o-cresol
B. Reimer-Tiemann carboxylation
C. Duff reaction
D. Kolbe-Schmidt reaction

Answer

To determine which of the following reactions does not form salicylic acid, we will analyze each reaction step by step.

### Step 1: Analyze the First Reaction
- **Reaction**: O-cresol (ortho-cresol) is oxidized using potassium permanganate (KMnO4) in the presence of a base (OH-) and heat.
- **Outcome**: The methyl group (CH3) of O-cresol is oxidized to a carboxylic acid (COOH), resulting in the formation of salicylic acid (C6H4(OH)(COOH)).

**Conclusion**: This reaction produces salicylic acid.

### Step 2: Analyze the Second Reaction
- **Reaction**: Riemann-Tiemann carboxylation of phenol is performed using NaOH or KOH and carbon tetrachloride (CCl4).
- **Outcome**: The phenol undergoes a reaction that leads to the formation of salicylic acid after hydrolysis.

**Conclusion**: This reaction also produces salicylic acid.

### Step 3: Analyze the Third Reaction (Duff Reaction)
- **Reaction**: Phenol is reacted with hexamethylenetetramine (HMTA) in the presence of an acid.
- **Outcome**: The product of this reaction is salicylaldehyde (C6H4(OH)(CHO)), not salicylic acid.

**Conclusion**: This reaction does not produce salicylic acid.

### Step 4: Analyze the Fourth Reaction
- **Reaction**: Phenol is reacted with CO2 in the presence of a base (NaOH or KOH) followed by hydrolysis.
- **Outcome**: This reaction leads to the formation of salicylic acid.

**Conclusion**: This reaction produces salicylic acid.

### Final Conclusion
Among the four reactions analyzed, the **third reaction (Duff Reaction)** does not form salicylic acid.

### Summary of Results
1. First Reaction: Produces salicylic acid.
2. Second Reaction: Produces salicylic acid.
3. Third Reaction (Duff Reaction): Does not produce salicylic acid.
4. Fourth Reaction: Produces salicylic acid.

Thus, the answer to the question is that the Duff Reaction does not form salicylic acid.

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