Stereoselective Synthesis of the Taxane Ring System via the Tandem Diels−Alder Cycloaddition
作者:Jeffrey D. Winkler、Hak Sung Kim、Sanghee Kim、Kaori Ando、Kendall N. Houk
DOI:10.1021/jo961620e
日期:1997.5.1
The application of the tandem Diels-Alder cycloaddition to the stereoselective synthesis of the tricyclic ring system of the taxane diterpenes is described. The exceedingly direct, two-step synthesis of the B/C cis-fused taxane nucleus in 50% overall yield from the reaction of two readily available acyclic precursors underscores the efficiency of this approach. A critical feature of the second, intramolecular
描述了串联的Diels-Alder环加成反应在紫杉烷二萜三环体系立体选择合成中的应用。B / C顺式融合的紫杉烷核的直接直接的两步合成,由两种容易获得的无环前体的反应以50%的总收率强调了这种方法的效率。第二个分子内Diels-Alder环加成反应的关键特征是立体化学信息通过紫杉烷骨架的传递,即从C环到A环的传递。顺式和反式二取代的C环结构的环加成导致建立紫杉烷合成所必需的C-1 / C-3相对立体化学。提出了一种计算模型以解释在这些反应中观察到的高水平的不对称诱导。