Q48 · CSIR-NET Chemistry, June 2017
Paper: CSIR-NET June 2017 · Subject: Organic Chemistry · Chapter: Pericyclic Reactions · Topic: Sigmatropic Shifts · Marks: 2 · Difficulty: Medium
Following reaction is an example of 
(a)Ramberg-Backlund reaction
(b)[2, 3]-sigmatropic shift
(c)[3, 3]-sigmatropic shift
(d)Pummerer rearrangement
Answer
Answer: B ✓ checked by 4AB · confidence high
Explanation
t-BuOK deprotonates the allylic sulfonium salt to a sulfur ylide, which undergoes a [2,3]-sigmatropic (Sommelet–Hauser/Doyle-type) rearrangement.
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