BF 3 ·CH 3 NO 2介导的多烯级联环化反应。通过非功能化3°烯烃的阳离子引发直接立体定向合成多环中间体的非常规高效方法。在(±)-紫杉二酮的全合成中的应用。
摘要:
BF 3气体在硝基甲烷中的便捷储备溶液已显示出可促进“ H +催化”多烯环化反应,并以极佳的区域和立体控制水平进行。甲直接这种新方法的用于实现阳离子polyannulations若干现代以及经典程序相比,已经结论性地确定的BF的制备优点3 ·CH 3 NO 2平台。描述了这些新条件用于阳离子多环化的简明全合成抗肿瘤药(±)-紫杉二酮。
A new access to trans-syn-trans perhydrophenanthrenic systems. Synthesis of (9βH)-8α-methylpodocarpan-13-one
作者:Jean-Marc Weibel、Denis Heissler
DOI:10.1016/0040-4039(94)85084-4
日期:1994.1
(9βH)-8α-Methylpodocarpan- 13-one has been synthesized from a 9,10-syn bicyclic precursor by a reaction sequence including an intramolecular Horner-Wadsworth-Emmons reaction — to form (9βH)-podocarp-8(14)-en-13-one — and an hydroxy-directed cyclopropanation to introduce the 8-methyl group on the less accessible α side of the molecule.