Q3(b)(ii). Classify the rearrangement at 33 °C
Classify the following sigmatropic rearrangement (at 33 °C) and comment on whether it is symmetry-allowed or symmetry-forbidden. [structure of the bicyclic diene given in the paper]
Answer in brief
It is a [3,3]-sigmatropic (Cope) rearrangement of a cis-divinylcyclopropane; thermally symmetry-allowed.
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Covers[3,3]-sigmatropicCope rearrangementdivinylcyclopropanesymmetry-allowedboat transition state
All parts of Question 3
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- 3(b)(ii) Classify the rearrangement at 33 °C5 marks
- 3(b)(iii) Methoxy methyl benzoquinone with butadiene5 marks
- 3(c)(i) Acyl chloride to isocyanate; singlet and triplet nitrene10 marks
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