Which one of the products of the following reactions does not react with Hingberg reagent to form sulphonamide?
(A)(see structure)
(B)(see structure)
(C)(see structure)
(D)(see structure)✓ Correct
Answer: (D)
Solution
Hinsberg's reagent, benzenesulphonyl chloride, can make a sulphonamide only with a nitrogen that still carries hydrogen, that is with a primary or a secondary amine. Hydrogen over nickel reduces 3-methylbenzonitrile to the primary amine 3-methylbenzylamine; lithium aluminium hydride reduces both functional groups of 4-formylbenzonitrile, giving a primary amine beside a primary alcohol; and sodium amalgam in ethanol likewise carries 4-nitrobenzonitrile through to an amine. Tin(II) chloride with hydrogen chloride, however, is the Stephen reduction, which halts at the aldimine, and hydrolysis of that intermediate gives benzaldehyde, a product with no nitrogen at all. The product that cannot form a sulphonamide is the benzaldehyde obtained from benzonitrile with tin(II) chloride and hydrogen chloride.
JEE Main · 2021 · 25 Jul 2021 · Shift 1 · Single correct option
