Kinetic Resolution of Aziridines Enabled by N‐Heterocyclic Carbene/Copper Cooperative Catalysis: Carbene Dose‐Controlled Chemo‐Switchability
作者:Zi‐Jing Zhang、Yu‐Hua Wen、Jin Song、Liu‐Zhu Gong
DOI:10.1002/anie.202013679
日期:2021.2.8
dynamic kinetic asymmetric transformation (DyKAT) are alternative and complementary avenues to access chiral stereoisomers of both starting materials and reaction products. The development of highly efficient chiral catalytic systems for kinetically controlled processes has therefore been one of the linchpins in asymmetric synthesis. N‐heterocyclic carbene (NHC)/copper cooperative catalysis has enabled
催化动力学拆分(KR)和动态动力学不对称转化(DyKAT)是获取原料和反应产物的手性立体异构体的替代途径和补充途径。因此,用于动力学控制方法的高效手性催化系统的开发一直是不对称合成的关键之一。N-杂环卡宾(NHC)/铜协同催化作用通过与异黄酮衍生的Enals进行[3 + 3]环化,使外消旋N-甲苯磺酰氮丙啶具有高效的KR和DyKAT,从而导致高度对映体富集的N-甲苯磺酰氮丙啶衍生物(高达99%以上)ee)和具有高结构多样性和立体选择性(最大> 95:5 dr,> 99%的螺环吲哚衍生物的大型文库)ee)。机理研究表明,NHC可以可逆地与铜催化剂结合,而不会损害其催化活性并调节铜络合物的催化活性,从而在KR和DyKAT之间切换化学选择。