Modular POP Ligands in Rhodium-Mediated Asymmetric Hydrogenation: A Comparative Catalysis Study
作者:José L. Núñez-Rico、Pablo Etayo、Héctor Fernández-Pérez、Anton Vidal-Ferran
DOI:10.1002/adsc.201200477
日期:2012.11.12
Highly efficient and enantioselectivehydrogenation reactions for α-(acylamino)acrylates, itaconic acid derivatives and analogues, α-substituted enolester derivatives, and α-arylenamides (25 substrates) catalyzed by chiral cationic rhodium complexes of a set of POP ligands have been developed. The catalytic systems derived from these POP ligands provided a straightforward access to enantiomerically
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–phosphoramiditeligands 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。
Enantiodivergent asymmetric catalysis with the tropos BIPHEP ligand and a proline derivative as chiral selector
作者:P. Oczipka、D. Müller、W. Leitner、G. Franciò
DOI:10.1039/c5sc03465e
日期:——
Enantiomer on demand: tropos ligand BIPHEP and chiral selector (S)-proline methyl ester allow enantiodivergent Rh-catalysed hydrogenation and asymmetric styrene hydroboration.
Synthesis of Phospholane-Phosphoramidite Ligands and their Application in Asymmetric Catalysis
作者:Tim Hammerer、Walter Leitner、Giancarlo Franciò
DOI:10.1002/cctc.201500070
日期:2015.5.18
A set of phospholane–phosphoramidite ligands, which possess four elements of chirality, has been synthesized through a modular diastereoselective process. The ligands were applied in the Rh‐catalyzed asymmetric CC hydrogenation of several functionalized olefins with enantioselectivities of up to 99 % ee and a turnover frequency of up to 12 000 h−1, in the Rh‐catalyzed hydroformylation of vinyl arenes
通过模块化的非对映选择性过程合成了一组具有四个手性元素的磷环-磷酰胺配体。该配体被用于对映体选择性高达99%ee和周转频率高达1200 h -1的几种官能化烯烃的Rh催化不对称CC氢化反应中 ,用于Rh催化具有对映选择性的乙烯基芳烃的加氢甲酰化反应高达79% ee的对映体,在Ir催化的不同芳基亚胺的不对称CN加氢中,对映体选择性高达ee的79% 。
Bidentate Phosphine-Phosphoramidite Ligands of the BettiPhos Family for Rh-Catalyzed Asymmetric Hydrogenation
Phosphine–phosphoramidite BettiPhosO ligands comprising a stereogenicphosphorusatom at the phosphoramidite moiety and a Betti base as chiral backbone have been used in the Rh‐catalyzed hydrogenation of functionalized olefins, leading to high enantioselectivities between 91 and 97 % ee confirming the effectiveness of the Betti base as valuable synthon for chiral phosphorus ligands.