Isoquinoline-based diimine ligands for Cu(II)-catalyzed enantioselective nitroaldol (Henry) reactions
作者:Michael J. Rodig、Hwimin Seo、Dimitri Hirsch-Weil、Khalil A. Abboud、Sukwon Hong
DOI:10.1016/j.tetasy.2011.05.018
日期:2011.5
A series of isoquinoline-based chiral diimine ligands are conveniently prepared via Bischler–Napieralski cyclization. The C2-symmetric diimine ligand 1a is effective in Cu(II)-catalyzedenantioselectiveHenryreactions between nitromethane and various aldehydes (11 examples), showing 50–89% yield and 75–93% ee.
Development of Biisoquinoline-Based Chiral Diaminocarbene Ligands: Enantioselective S<sub>N</sub>2‘ Allylic Alkylation Catalyzed by Copper−Carbene Complexes
作者:Hwimin Seo、Dimitri Hirsch-Weil、Khalil A. Abboud、Sukwon Hong
DOI:10.1021/jo702512z
日期:2008.3.1
Chiral biisoquinoline-based diaminocarbene ligands (BIQ) were designed to create a chiral environment extended toward the metal center, which was confirmed by an X-ray structure. The concise ligand synthesis is highlighted by a modified Bischler−Napieralski cyclization of bisamides prepared from readily available chiral phenethylamines, and allows easy variation of the stereodifferentiating groups
设计基于手性双异喹啉的二氨基碳烯配体(BIQ),以创建向金属中心延伸的手性环境,这通过X射线结构得以证实。简明的配体合成是由易得的手性苯乙胺制备的双酰胺的Bischler-Napieralski环的修饰Bischler-Napieralski环合突出显示的,并且可以轻松改变立体分化基团。环己基-BIQ-铜配合物是使用Grignard试剂进行对映选择性S N 2'烯丙基烷基化的有效催化剂,显示出S N 2'区域选择性高于5:1,对映选择性在68-77%ee范围内。