Coupling reaction is an example of

Step-by-step solution

Coupling reactions, such as the formation of azo dyes from diazonium salts and aromatic compounds (like phenols or amines), involve the attack of a diazonium cation on an electron-rich aromatic ring. The diazonium cation, Ar-N₂⁺ , acts as a weak electrophile. It attacks the electron-rich aromatic ring, which acts as a nucleophile. This process results in the replacement of a hydrogen atom on the aromatic ring by the diazonium group, which is a characteristic feature of electrophilic aromatic substitution. Therefore