JEE MainChemistryAmines
An orange-red dye has the chemical name 4-(phenylazo)-1-naphthol. Which of the following sets of reactants and conditions will produce this dye as the major product?
Options
- A1-Naphthylamine with NaNO ₂/ HCl at 0-5^ C , followed by reaction with phenol in alkaline medium
- BAniline with NaNO ₂/ HCl at 0-5^ C , followed by reaction with -naphthol in alkaline medium
- CAniline with NaNO ₂/ HCl at 0-5^ C , followed by reaction with -naphthol in alkaline medium
- D2-Naphthylamine with NaNO ₂/ HCl at 0-5^ C , followed by reaction with phenol in alkaline medium
Correct answer
C. Aniline with NaNO ₂/ HCl at 0-5^ C , followed by reaction with -naphthol in alkaline medium
Step-by-step solution
The structure of 4-(phenylazo)-1-naphthol indicates an azo linkage ( -N=N- ) connecting a phenyl ring and a 1-naphthol ring at its 4-position. In retrosynthetic analysis of azo dyes, the bond is cleaved at the azo group. The aromatic ring with the activating group ( -OH ) acts as the coupling component, while the other ring originates from the diazonium salt. Here, the coupling component is -naphthol (1-naphthol), which undergoes electrophilic aromatic substitution at the para position (C-4) due to the strong activ