Q3 · CSIR NET Chemistry, December 2011
Paper: CSIR NET December 2011 · Subject: Organic Chemistry · Chapter: Reagents, Reaction Mechanisms & Named Reactions · Topic: Reagents, Reaction Mechanisms & Named Reactions – General · Marks: 2 · Difficulty: Medium
The reaction given below proceeds through 
(a)
(b)
(c)
(d)
Answer
Answer: A ✓ checked by 4AB · confidence medium
Explanation
I₂ adds to the exo face of the norbornene double bond to form an iodonium ion. The endo carboxylate then opens it from the opposite (endo) face, giving the iodolactone. The intermediate is the exo-iodonium ion (a).
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