SYNTHESIS AND [2+2]-CYCLOREVERSION OF CAGE KETONES
作者:Yoshiro Yamashita、Toshio Mukai
DOI:10.1246/cl.1984.1741
日期:1984.10.5
A series of pentacyclic cageketones 2b-d having no substituent was synthesized by the photochemical [2+2]-cycloaddition reaction of corresponding tricyclic dienones 1b-d. The cageketones 2b-d underwent thermal [2+2]-cycloreversion to give dienones 1b-d. The reactivities were dependent on the length of the bridge “X”.
Asymmetric [2+2+1] cyclopentannulation of olefins. Ring expansion of 2-N-methyl-N-tosyl-cyclobutanone
作者:Florence Mahuteau-Betzer、Léon Ghosez
DOI:10.1016/s0040-4020(02)00694-4
日期:2002.8
factors which have been analyzed. Treatment of these oxiranes with a stoichiometric amount of lithium iodide in refluxing tetrahydrofuran gave excellent yields of monocyclic or fused cyclopentenones 4 resulting from a β-elimination of N-methyl-N-tosylamide from a primarily formed cyclopentanone. The ring-expansion was totally selective but for oxiranes attached to a bicyclo[4.2.0]octanone system. In all