New Cobalt-Catalyzed Cycloisomerization of ε-Acetylenic β-Keto Esters. Application to a Powerful Cyclization Reactions Cascade
作者:Paul Cruciani、Robert Stammler、Corinne Aubert、Max Malacria
DOI:10.1021/jo9600619
日期:1996.1.1
type reaction of epsilon-acetylenic beta-keto esters to form highly functionalized methylenecyclopentanes are described. The observed regio-, chemo-, and stereoselectivities support a process of cycloisomerization which controls the relative stereochemistry of two contiguous stereogenic centers. An efficient route to the basic skeleton of the phyllocladane family has been achieved via a one-pot sequence
描述了研究钴(I)催化ε-乙炔β-酮酸酯形成高度官能化的亚甲基环戊烷的烯型反应的全部细节。观察到的区域,化学和立体选择性支持环异构化的过程,该过程控制两个连续的立体发生中心的相对立体化学。通过一锅法环化序列已经实现了通往叶绿素家族基本骨架的有效途径:烯型,[2 + 2 + 2],[4 + 2]。这种新的级联反应是从一个容易获得的无环多不饱和前体以完全立体选择性的方式产生六个碳-碳键和四个环。