Photochemical reactions. 132nd communication. Photochemistry of 5,6‐epoxy‐5,6‐dihydro‐7‐methyl‐β‐ionine: Influence of a methyl group at the enone side chain on the oxirane cleavage
- 1 February 1984
- journal article
- research article
- Published by Wiley in Helvetica Chimica Acta
- Vol. 67 (1) , 120-128
- https://doi.org/10.1002/hlca.19840670115
Abstract
1n, π*‐Excitation of the γ,δ‐epoxy‐enone (E)‐3 leads exclusively to the conformers (Z)‐3A + B. On 1π, π*‐excitation of (E)‐3, in addition to (Z)‐3A + B, products 6–9 arising from a carbene intermediate e are formed. However, products of an isomerization via C(γ), O‐bond cleavage of the oxirane were not formed on either mode of excitation. On thermolysis, at 80° the conformer (Z)‐3A is transformed into (Z)‐3B, which on photolysis returns to (Z)‐3A and (E)‐3. At 160°, however, (Z)‐3B rearranges to the isomers 6, 10 and 11.Keywords
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