Q94 · CSIR-NET Chemistry, June 2011
Paper: CSIR-NET June 2011 · Subject: Organic Chemistry · Chapter: Pericyclic Reactions · Topic: Sigmatropic Shifts · Marks: 2 · Difficulty: Medium
The reaction given below is an example of 
(a)1,3-sigmatropic hydrogen shift
(b)1,3 -sigmatropic methyl shift
(c)1,5 sigmatropic hydrogen shift
(d)1,5-sigmatropic methyl shift.
Answer
Answer: C ✓ checked by 4AB · confidence high
Explanation
5-Methylcyclopentadiene isomerises to the 1-methyl isomer by suprafacial [1,5]-H shifts (c).
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