Copper-Catalyzed Cyclization-Fragmentations of Enynols
作者:Charles Fehr、Magali Vuagnoux、Horst Sommer
DOI:10.1002/chem.201002314
日期:2011.3.28
Pt and Au are going out of fashion: The [Cu(CH3CN)4][BF4] species effectively catalyzes the cyclization–fragmentation of 5‐en‐1‐yn‐3‐ols. The reactivity of 6‐en‐1‐yn‐4‐ols greatly depends on the catalyst used (see scheme). An unusual fragmentation and metathesis reactions of 6‐en‐1‐yn‐4‐ols have also been detected.
Pt和Au不合时宜:[Cu(CH 3 CN)4 ] [BF 4 ]物种有效催化5烯1炔3醇的环化片段化。6 en 1 yn 4 ols的反应性在很大程度上取决于所使用的催化剂(参见方案)。还检测到6 en 1 yn 4 ols的异常断裂和易位反应。
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 chiralitytransfer. We confirm a mechanism by means of cyclization