Q106 · CSIR-NET Chemistry, December 2019
Paper: CSIR-NET December 2019 · Subject: Organic Chemistry · Chapter: Pericyclic Reactions · Topic: Electrocyclic · Marks: 2 · Difficulty: Medium
The following transformation involves a series of 
+ 
+ 
+ + (a)electrocyclic ring-opening and closing reaction
(b)cycloaddition and cycloreversion reactions
(c)sigmatropic rearrangements
(d)cheletropic reaction and elimination reaction
Answer
Answer: B ✓ checked by 4AB · confidence high
Explanation
A Diels–Alder cycloaddition with the pyrone is followed by a retro-Diels–Alder cycloreversion that expels CO₂ — a sequence of cycloaddition and cycloreversion.
Study loop for Pericyclic Reactions