Hung-Chun Lin, R. Tsai, Hsiao-Pin Wu
Jan 7, 2016
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0
Influential Citations
10
Citations
Journal
Tetrahedron
Abstract
1,2-Disubstituted cyclopropene, 1-methyl-2-phenylcyclopropene (18), was generated by bromo-lithium exchange of 1-bromo-2-phenylcyclopropene followed by treatment with methyl iodide. Compound 18 was oxidized by oxygen to give the α,β-unsaturated carbonyl product 25 and diketone 27 and the tautomeric, β-hydroxyl-α,β-unsaturated ketone 28. However, compound 28 reacted further with the cyclopropene 18 in a retro-Claisen-like reaction to generate adduct 26. Furthermore, compound 18 underwent ene dimerization in neat condition to form the endo-dimer 40 and exo-dimer 41 followed by oxidization with oxygen to give aldehyde 39. It is noteworthy that the endo-dimer 40 and exo-dimer 41 could be trapped with thiophenol to give adduct 42 and 43. In addition, the ene reaction of exo-dimer 41 with monomer 18 gave an exo-exo ene trimer 46 through an exo-transition state which was also trapped by thiophenol to give adducts 44 and 45.