System oriented design of triquinanes: stereocontrolled synthesis of pentalenic acid and pentalenene
作者:T. Hudlicky、G. Sinai-Zingde、M.G. Natchus、B.C. Ranu、P. Papadopolous
DOI:10.1016/s0040-4020(01)87747-4
日期:1987.1
internal cyc1opropanation of dienes 23 or cyc1opropanation of enone 25 followed by the thermolytic rearrangements of cyclopropanes 24, 39, 42, 45, and 48 to furnish triquinanes 26 and 40. An investigation of electronic effects affecting the diradical cleavage of viny1cyclopropanes was performed. The triquinanes 26 or 40 were transformed to the title compounds by reductive operations at C-9. The equilibration
使用[4 + 1]和[2 + 3]环戊烯环化方法分别合成了戊烯酸5和戊烯4以及它们的C-9差向异构体5a和4a。的关键步骤涉及二烯的内部cyc1opropanation 23或烯酮cyc1opropanation 25随后环丙烷的热分解重排24,39,42,45,和48至配料triquinanes 26和40。研究了影响viny1环丙烷双自由基裂解的电子效应。三喹烷通过在C-9下的还原操作将26或40转化为标题化合物。在C-9酯60的平衡是在分子力学预测中简要讨论的,该预测涉及天然对Epi系列中C-9构象的热力学稳定性。在每个系列中,天然烃及其C-9差向异构体的立体选择性均优于9:1。