Major product 'P' formed in the following reaction is:
Hydrocarbons · Class 11 · JEE Main Previous Year Question
Major product 'P' formed in the following reaction is:
- a
- b✓
- c
- d
Step 1: Identify the starting material
The starting material is pent-4-enoic acid () treated with .
Step 2: Reaction of unsaturated acid with Br2
When an unsaturated carboxylic acid reacts with , the carboxylate anion can act as an internal nucleophile after bromonium ion formation.
Answer: Option (b) — Lactone with Br
Key Points to Remember:
- Unsaturated carboxylic acids + : lactone formation via intramolecular nucleophilic attack
- 5-membered and 6-membered lactones are most stable
- The acts as an intramolecular nucleophile toward the bromonium ion
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