Question

Answer the question on the basis of the passage given below: 
Alcohols and phenols are formed when a hydrogen atom in a hydrocarbon, aliphatic and aromatic respectively, is replaced by \(-OH\). The substitution of a hydrogen atom in a hydrocarbon by an alkoxy or aryloxy group forms ethers. 
Alcohols and phenol consist of two parts, an alkyl/aryl group and a hydroxyl group. The properties of alcohols and phenols are primarily due to the hydroxyl group. The nature of alkyl and aryl groups simply modify these properties. Alcohol react both as nucleophiles and electrophiles whereas in phenols, the reactions that take place on the aromatic ring are electrophilic substitution reactions. 
Name the given reaction: 
 
\[ \text{Phenol} + \text{CH}_3\text{Cl} + \text{aq.NaOH} \xrightarrow{\text{340K}} \text{Salicylaldehyde} \] 

• A. Williamson's synthesis
• B. Kolbe's reaction
• C. Reimer-Tiemann reaction
• D. Sandmeyeras reaction

Hint:

The Reimer-Tiemann reaction is a useful method for introducing a formyl group (-CHO) into the ortho position of phenols. This reaction is distinct from other aromatic substitution reactions, such as the Kolbe reaction, where a carboxyl group is introduced.

Answer 1

The Correct Option is C

The reaction shown is a Reimer-Tiemann reaction, which involves the electrophilic substitution of the hydroxyl group on the aromatic ring with a formyl group (–CHO) in the presence of chloroform (CHCl₃) and sodium hydroxide (NaOH) under heat. This leads to the formation of salicylaldehyde. The Reimer-Tiemann reaction is typically used to introduce a formyl group into an aromatic ring, particularly phenols. The chemical equation for the reaction is: \[ \text{Phenol} + \text{CH}_3\text{Cl} + \text{aq.NaOH} \xrightarrow{340K} \text{Salicylaldehyde} \] The product, salicylaldehyde, is a result of the formylation of phenol.