Synthesis of (−)-Cubebol by Face-Selective Platinum-, Gold-, or Copper-Catalyzed Cycloisomerization: Evidence of Chirality Transfer and Mechanistic Insights
作者:Charles Fehr、Beat Winter、Iris Magpantay
DOI:10.1002/chem.200901292
日期:2009.9.28
describe in detail a direct, stereoselective synthesis of (−)‐cubebol based on a Pt‐, Au‐, or Cu‐catalyzed cycloisomerization in which control of the configuration of the propargylic center is essential for the facial selectivity. In addition, we show that cycloisomerization reactions of enantioenriched propargyl pivalates occur with substantial chirality transfer. We confirm a mechanism by means of cyclization
我们详细描述了基于Pt,Au或Cu催化的环异构化的(-)-立方醇的直接,立体选择性合成,其中对炔丙基中心构型的控制对于面部选择性至关重要。另外,我们表明,对映体富集的炔丙基新戊酸酯的环异构化反应以大量的手性转移发生。我们通过环化以及随后的[1,2]-酰基迁移,确定了Pt和Au催化的环异构化的机理。到目前为止,没有证据支持Cu催化的环异构化遵循相同的反应过程。