Chapter 23, Problem 68PP

Interpretation Introduction

Interpretation: The given azo dye, alizarine yellow R has to be prepared via an azo coupling reaction from the starting materials which have to be identified.

Concept Introduction:

Aryldiazonium salts on coupling with an activated aromatic ring give an azo dye which produces a deep color in the final product.  This color is due to the extended conjugation in it.  This reaction occurs by electrophilic substitution reaction.  This method is called an azo coupling.  The obtained final compound is known as azo dyes.

To find: Identify the reactants involved in the formation of alizarine yellow R, an azo dye via an azo coupling reaction

Determine the ring which is more strongly activated