Tandem Use of Cobalt-Mediated Reactions to Synthesize (+)-Epoxydictymene, a Diterpene Containing a <i>Trans</i>-Fused 5−5 Ring System
作者:Timothy F. Jamison、Soroosh Shambayati、William E. Crowe、Stuart L. Schreiber
DOI:10.1021/ja970022u
日期:1997.5.1
(+)-epoxydictymene has been synthesized in 20 steps using the asymmetry of (R)-pulegone and several substrate-controlled diastereoselective reactions to prepare the natural product in its natural configuration. Three of the four rings were assembled with two consecutive intramolecular reactions involving dicobalt hexacarbonyl complexes of alkynes: a Lewis acid-promoted Nicholas reaction and a Pauson−Khand reaction
二萜 (+)-epoxydictymene 已使用 (R)-pulegone 的不对称性和几种底物控制的非对映选择性反应在 20 个步骤中合成,以制备其天然构型的天然产物。四个环中的三个通过涉及炔烃的六羰基二钴配合物的两个连续分子内反应组装:路易斯酸促进的尼古拉斯反应和 Pauson-Khand 反应。天然产物的应变反式-3-氧杂双环[3.3.0]辛烷环系统的构建提出了重大挑战。为此,研究了几种自由基和阴离子环化,后者导致 (+)-epoxydictymene。