Construction of the Tricyclic Furanochroman Skeleton of Phomactin A via the Prins/Conia-Ene Cascade Cyclization Approach
作者:Shuangping Huang、Guangyan Du、Chi-Sing Lee
DOI:10.1021/jo200644t
日期:2011.8.19
asymmetric Prins/Conia-ene cascade cyclization has been developed with In(OTf)3 in CH3CN from 0 to 70 °C. These conditions afforded very good yields of the 1-oxadecalin product in one pot and effectively suppressed the racemization of the 1-oxadecalin product with almost no enantiomeric excess (ee) loss. This cascade cyclization has been successfully employed for the construction of the highly functionalized
用In(OTf)3在CH 3中开发了底物控制的不对称Prins / Conia-ene级联环化反应CN从0到70°C。这些条件使一锅中的1-oxadecalin产品的收率非常好,并有效地抑制了1-oxadecalin产品的消旋作用,几乎没有对映体过量(ee)的损失。通过一锅操作(66%的收率,单一的非对映异构体),这种级联环化已成功用于以无环β-酮酯和炔基为底物的高蛋白功能化的光蛋白A的1-oxadecalin单元的构建。在非常温和的条件下,可以通过三步,以52%的收率通过环氧化/脱烷氧羰基化方案,将1-oxadecalin部分轻松转化为phomactin A的三环呋喃铬烷骨架。