发现钯催化的 1,1-二硼基-1-烯烃与芳基和烯基碘化物的交叉偶联反应立体选择性地进行,产生相应的单偶联产物,作为具有 E 构型的单个非对映异构体。初始产物与另一种芳基碘化物的第二次偶联得到立体化学纯形式的各种三芳基烯烃。这种三芳基烯烃的高度立体选择性方法允许人们在一个锅中从 1,1-二硼基-1-烯烃合成两种非对映异构体。
Multisubstituted olefins are efficiently prepared by the zirconocene-mediated regio- and stereoselective coupling between 1-alkynylboronates and ethylene, followed by sequential transformation in moderate to high yields. The proper combination of substrates and reaction conditions is important for high yields. The synthesis of various tetrasubstituted alkenes in a regio- and stereocontrolled manner
Diversity-Oriented Synthesis of Tamoxifen-type Tetrasubstituted Olefins
作者:Kenichiro Itami、Toshiyuki Kamei、Jun-ichi Yoshida
DOI:10.1021/ja037566i
日期:2003.12.1
A general synthetic scheme for tamoxifen-typetetrasubstitutedolefins based on the novel Cu-catalyzed carbomagnesation acrossalkynyl(2-pyridyl)silane has been developed. A wide array of electronically and structurally diverse tetrasubstitutedolefins can be prepared in a regiocontrolled, stereocontrolled, and diversity-oriented manner. Noteworthy features are that (i) the three aryl groups, which
已经开发了基于新型 Cu 催化的炔基(2-吡啶基)硅烷碳镁化反应的他莫昔芬型四取代烯烃的一般合成方案。可以以区域控制、立体控制和面向多样性的方式制备各种电子和结构不同的四取代烯烃。值得注意的特征是 (i) 被认为对抗雌激素活性很重要(必不可少)的三个芳基可以随意变化,因为它们都源于容易获得的芳基碘化物,以及 (ii) 任何立体和原则上,区域异构体可以通过简单地改变芳基碘化物的应用顺序来制备。