Question

Formation of p-hydroxyazobenzene from benzene diazonium chloride and phenol in mild alkaline medium is

• A. Nucleophilic substitution
• B. Electrophilic addition
• C. Nucleophilic addition
• D. Electrophilic substitution

Hint:

Electrophilic substitution reactions are common with aromatic compounds like benzene and phenol, where the electrophile attacks the ring and replaces a hydrogen atom.

Answer 1

The Correct Option is D

Step 1: Understanding the reaction mechanism.
The formation of p-hydroxyazobenzene from phenol and benzene diazonium chloride occurs via an electrophilic substitution mechanism. In this reaction, the electrophilic diazonium ion attacks the phenol ring at the para position, forming the final product.
Step 2: Analyzing the options.
(A) Nucleophilic substitution: This is incorrect. The reaction involves electrophilic substitution, not nucleophilic substitution.
(B) Electrophilic addition: This is incorrect, as the reaction is a substitution, not an addition.
(C) Nucleophilic addition: This is incorrect. The reaction is electrophilic, not nucleophilic.
(D) Electrophilic substitution: This is correct. The reaction proceeds through an electrophilic substitution mechanism, where the diazonium ion attacks the phenol ring.
Step 3: Conclusion.
The correct answer is (D) Electrophilic substitution.