Quinaphos and Dihydro-Quinaphos Phosphine-Phosphoramidite Ligands for Asymmetric Hydrogenation
作者:Thomas Pullmann、Barthel Engendahl、Ziyun Zhang、Markus Hölscher、Antonio Zanotti-Gerosa、Alan Dyke、Giancarlo Franciò、Walter Leitner
DOI:10.1002/chem.201000063
日期:2010.7.5
Quinaphos ligands and the related Dihydro‐Quinaphos ligands based on the more flexible 1,2,3,4‐tetrahydroquinoline backbone have been prepared and fully characterised. A general and straightforward separation protocol was devised, which allowed for the gram‐scale isolation of the Ra,Sc and Sa,Rc diastereomers. These new phosphine–phosphoramidite ligands have been applied in the Rh‐catalysed asymmetric hydrogenation
基于更灵活的1,2,3,4-四氢喹啉骨架,已经制备了喹喔啉配体和相关的二氢喹喔啉配体的新衍生物并进行了充分表征。设计了一种通用且直接的分离方案,该方案可实现R a,S c和S a,R c非对映异构体的克级分离。这些新的膦-亚磷酰胺配体已用于Rh催化的官能化烯烃的不对称加氢反应,在大多数情况下均具有出色的对映选择性(≥99%),周转频率(TOF)值高达≥20000 h -1。这些结果证实了容易获得的喹喔啉型配体的实用性,该类配体属于迄今为止已知的Rh催化加氢活性最强和选择性最高的一类。