In Reimer - Tiemann reaction the major produc is

Options

A. Ortho isomer due to intra molecular H-bonding
B. Meta isomer
C. Para isomer due to symmetry
D. None of these

Explanation

To solve the question regarding the major product of the Reimer-Tiemann reaction, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding the Reaction**: The Reimer-Tiemann reaction involves the electrophilic substitution of phenol using chloroform (CHCl3) in the presence of a strong base, typically aqueous sodium hydroxide (NaOH).

2. **Formation of Phenoxide Ion**: In the presence of NaOH, phenol (C6H5OH) is deprotonated to form the phenoxide ion (C6H5O⁻Na⁺). This ion is more nucleophilic and can react more readily with electrophiles.

3. **Generation of Carbene**: Chloroform (CHCl3) reacts with the base to generate a dichlorocarbene (:CCl2). This carbene acts as an electrophile that can attack the phenoxide ion.

4. **Electrophilic Attack**: The carbene (:CCl2) attacks the ortho or para positions of the phenoxide ion. However, due to steric and electronic factors, the ortho position is favored for substitution.

5. **Formation of Intermediate**: The product of this electrophilic substitution is an intermediate compound that contains both the phenolic group and the carbene.

6. **Hydrolysis and Rearrangement**: Upon further reaction with water (from the aqueous NaOH), the intermediate undergoes hydrolysis, leading to the formation of an aldehyde.

7. **Final Product**: The major product of the Reimer-Tiemann reaction is salicylaldehyde (ortho-hydroxybenzaldehyde), which has the aldehyde group (-CHO) at the ortho position relative to the hydroxyl group (-OH) on the benzene ring.

8. **Conclusion**: Therefore, the major product of the Reimer-Tiemann reaction is salicylaldehyde, which is an ortho isomer due to the positioning of the substituents.

### Final Answer:
The major product of the Reimer-Tiemann reaction is **salicylaldehyde** (ortho-hydroxybenzaldehyde).

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