The pagodane route to dodecahedranes: highly functionalized, saturated and bis-unsaturated pentagonal dodecahedranes via SN2 cyclizations
作者:Rolf Pinkos、Johann Peter Melder、Klaus Weber、Dieter Hunkler、Horst Prinzbach
DOI:10.1021/ja00069a015
日期:1993.8
saturated dodecahedranes featuring novel substitution patterns-two (45), four (42 and 44), and six (40, 41, and 43) skeletal positions being pairwise functionalized-are synthesized starting from 14,19-dioxopagodane-4-syn,9-syn-dicarbonitrile (4). Crucial stages on the way from 4 to the key 1,16-dodecahedradiene 40 are the installation of anti-positioned leaving groups at C14(19) via pagodane bislactone
通过 SN 2 取代跨环环化在 bisseco(21 和 30-34)或 seco 前体底物(25 和 35-39)、(双)不饱和、环氧环化和饱和十二面体中具有新颖的取代模式 - 二 (45)从 14,19-dioxopagodane-4-syn,9-syn-dicarbonitrile (4) 开始合成四个(42 和 44)和六个(40、41 和 43)骨架位置成对官能化。从 4 到关键的 1,16-十二面二烯 40 的关键阶段是通过 pagodane 双内酯(4→5b→7b→11→3,总体平均 75%)在 C14(19) 上安装反定位离去基团和Pagodane→Bisseco二烯异构化(3→18→17→21,总体平均80%)。使用更短但不太快捷的 40 路线来制备仲十二面二烯