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。
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.
Crossed Regio‐ and Enantioselective Iron‐Catalyzed [4+2]‐Cycloadditions of Unactivated Dienes
作者:Elena Braconi、Nicolai Cramer
DOI:10.1002/anie.202112148
日期:2022.2.7
An enantioselective iron-catalyzed cross-[4+2]-cycloaddition of unactivated branched and linear dienes is described. The illustrated process provides a very efficient and atom-economic access to chiral 1,3-substituted vinyl-cyclohexenes under very mild reaction conditions. The development of a chiral bis-dihydroisoquinoline ligand class was essential to obtain excellent levels of chemo-, regio- and