TU Braunschweig, Institutes of Organic, Inorganic and Analytical Chemistry, Hagenring 30, 38106 Braunschweig, Germany.
Org Lett. 2010 Feb 19;12(4):784-7. doi: 10.1021/ol902854t.
The fully substituted 12-membered macrocycle of the cubitane-type diterpenoids has been assembled in an enantioselective manner following a novel "bridge-and-cut" strategy. Hydroxyalkylation of (S)-carvone afforded a carvonylgeraniol, which underwent transannular cyclization on treatment with samarium diiodide in THF. Fragmentation of one of the shorter bridges of the resulting [8.2.2]bicycle liberated the 12-membered ring with the desired cis-arrangement of the isopropenyl side chains.
全取代的 12 元大环杯[烷]型二萜通过一种新颖的“桥切”策略以对映选择性的方式进行了组装。（S）-香芹酮的羟烷基化得到了香芹醇香叶基醚，它在四氢呋喃中用二碘化钐处理进行了环丙烷环化。所得[8.2.2]双环的较短桥之一的断裂释放出具有所需的异丙烯基侧链顺式排列的 12 元环。
