JEE Advanced2026ChemistryAminesActual
Match the major products obtained in the reactions given in List-I with the corresponding structures in List-II and choose the correct option. List-I List-II (P) (1) (Q) (2) (R) (3) (S) (4) (5)
Options
- AP 2; Q 1; R 5; S 4
- BP 1; Q 2; R 4; S 5
- CP 1; Q 2; R 3; S 4
- DP 2; Q 1; R 3; S 5
Correct answer
B. P 1; Q 2; R 4; S 5
Step-by-step solution
For the reaction in (P), 2-bromo-5-nitrobenzaldehyde oxime reacts with aqueous NaOH. The strong base deprotonates the oxime group. The resulting oximate anion undergoes intramolecular nucleophilic aromatic substitution ( S_NAr ), attacking the ortho-carbon and displacing the bromide ion to form a 1,2-benzisoxazole intermediate. Since it is derived from an aldoxime, this intermediate has a hydrogen atom at the C3 position. In the presence of NaOH, it undergoes base-catalyzed Kemp elimination (ring opening) to form 2