Polyene cascade cyclizations mediated by BF3·CH3NO2. an unusually efficient method for the direct, stereospecific synthesis of polycyclic intermediates via cationic initiation at non-functionalized 3° alkenes. An application to the total synthesis of (±)-taxodione.
作者:Scott R. Harring、Tom Livinghouse
DOI:10.1016/s0040-4020(01)85502-2
日期:——
catalyzed” polyene cyclizations that proceed with excellent levels of regio- and stereocontrol. A direct comparison of this new method for effecting cationic polyannulations to several modern as well as classical procedures has conclusively defined the preparative advantages of the BF3·CH3NO2 medium. The utilization of these new conditions for cationic polycyclization in a concise totalsynthesis of the antineoplastic
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。