Intramolecular [4+3] Cycloadditions. Towards a Synthesis of Widdrol
摘要:
Certain substituted alkoxyallylic sulfones were alkylated and treated with Lewis acids to produce vinylthionium ions that underwent intramolecular [4+3] cycloaddition reactions with a tethered furan. Manipulation of the cycloadduct led to the synthesis of widdrol. Other attempts to prepare the cycloadducts were made, but none were exceptionally better than the route using vinylthionium ions as intermediates. Interesting aspects of the alkylation chemistry of phenylthio-substituted alkoxyallylic sulfones are detailed as well.
Photochemical reactions. 147th Communication. Further investigation of the photochemistry of 5,6-epoxy-5,6-dihydro-?-ionone: Product formationvia a carbonyl-ylide intermediate
作者:Anthony O'Sullivan、Bruno Frei、Oskar Jeger
DOI:10.1002/hlca.19860690305
日期:1986.5.7
On π,π*-excitation of the epoxyenone (E)-1 (λ = 254 nm, MeCN), in addition to the previously isolated compounds 2–9, the new products 10–12, derived from the ylide intermediate c were isolated. Further evidence for the ylide c was obtained by the rapid racemization of the optically active epoxyenone (−)-(E)-1.
Advances in bridged 1,2,4-trioxane-based chemistry. A divergent approach to oxa-heterocycles based on ambident reactivity
作者:Martín J. Riveira、Agustina La-Venia、Mirta P. Mischne
DOI:10.1016/j.tetlet.2009.11.135
日期:2010.2
Heterogeneous catalytichydrogenation of unsaturated 1,2,4-trioxanes derived from β-ionone-type dienones has been investigated. Our studies revealed a versatile reactivity of trioxanic substrates that led to the development of reaction methodology for the selective manipulation of the alkene and peroxide functionalities. Depending on the catalytic system used, divergent reaction pathways can be controlled
Chemistry of 1,2,4-Trioxanes: Metal-Induced Deoxygenation and Rearrangement of the 1,2,4-Trioxane Obtained by Photooxidation of β-Ionone
作者:Mirta Mischne
DOI:10.1055/s-2002-33637
日期:——
The reactivity of 2,2,6,8-tetramethyltricyclo(6.2.2.01,6)dodecene (2) toward different metal salts has been explored. In the presence of Fe(II), Sn(II) and Ce(IV) ions, compound 2 underwent a rearrangement process to afford acyclic triketones Z-3 and E-3. The action of Zn powder in acetic acid resulted in an unexpected formation of furan 4 in high yield.
Photochemische Reaktionen. 73. Mitteilung. Neuartige Photoreaktionen des (�)-trans-?-Jonon-epoxids
作者:Beat R. von Wartburg、Hans R. Wolf、Oskar Jeger
DOI:10.1002/hlca.19730560615
日期:1973.7.18
The racemic trans-β-ionone-epoxide (7) upon irradiation with light of wavelength 254 nm (in pentane solution) gives rise to novel photochemical processes and formation of compounds 12, 13, 14, and 15.