Question

What is the product of Riemer-Timer Reaction?

• A. Salicylaldehyde
• B. Salicylic Acid
• C. Phenol
• D. Bromobenzene

Answer 1

The Correct Option is A

Concept:
The Reimer-Tiemann reaction is a classic organic chemistry reaction used to form aldehydes from phenols. This reaction introduces a formyl group (-CHO) at the ortho position of the aromatic ring of phenol, forming salicylaldehyde as the major product.

Reaction Conditions:
• Phenol is treated with chloroform (CHCl₃)
• In the presence of aqueous sodium hydroxide (NaOH)
• Followed by acidic hydrolysis to complete the reaction

Chemical Reaction:
C₆H₅OH (phenol) + CHCl₃ + 3NaOH → C₆H₄(OH)(CHO) (salicylaldehyde) + 3NaCl + 2H₂O

Mechanism Summary:
1. **Generation of Dichlorocarbene (:CCl₂)** from chloroform under basic conditions.
2. The reactive intermediate attacks the electron-rich ortho position of the phenoxide ion.
3. Rearrangement and hydrolysis produce the final aldehyde group at the ortho position.

Product Formed:
The major product is salicylaldehyde, an aromatic compound with both a hydroxyl group (–OH) and an aldehyde group (–CHO) on adjacent carbon atoms.

Conclusion:
In the Reimer-Tiemann reaction, phenol reacts with chloroform and aqueous sodium hydroxide to form salicylaldehyde as the major product. This reaction is widely used in laboratories and industry to synthesize aromatic aldehydes.

Therefore, the correct option is: (A) Salicylaldehyde.