Amongst the compounds given, the one that would form a brilliant colored dye on treatment with in dil. HCl followed by addition to an alkaline solution of β-naphthol is
← IIT-JEE 2011 · Paper 2
ChemistrySingle correct+3 / -1Question 6 of 60
IIT-JEE 2011 · Paper 2, Chemistry question 6
Answer and worked solution
Official answer: C
Azo dyes need an aryl diazonium salt, which only a primary aromatic amine gives with /HCl at 0-5 °C. The diazonium ion then couples with β-naphthoxide.
- (A) is a tertiary amine and (B) a secondary amine (gives an N-nitrosamine).
- (D) benzylamine is a primary aliphatic amine; its diazonium salt decomposes at once.
- (C) p-toluidine is a primary aromatic amine and gives a red-orange azo dye.
(C)