Chiral phosphite–phosphoroamidites: a new class of ligand for asymmetric catalytic hydrogenation
作者:Montserrat Diéguez、Aurora Ruiz、Carmen Claver
DOI:10.1039/b109043g
日期:2001.12.19
A series of novel phosphite–phosphoroamidite ligands, derived from readily available D-xylose, has been used for the first time in the asymmetric Rh-catalyzed hydrogenation of a series of α,β-unsaturated carboxylic acid derivatives with excellent enantioselectivity (ee up to >99%).
Chiral furanoside phosphite–phosphoroamidites: new ligands for asymmetric catalytic hydroformylation
作者:Montserrat Diéguez、Aurora Ruiz、Carmen Claver
DOI:10.1016/s0957-4166(01)00489-x
日期:2001.11
We have designed a new series of phosphite phosphoroamidites ligands 1 4 based on a furanoside backbone. These ligands were screened in the Rh-catalyzed asymmetric hydroformylation of styrene, inducing high regioselectivities with 2-phenylpropanal md moderate enantioselectivities (up to 65%, c.e.). The results showed that the configuration of the stereogenic carbon atom C(3) at the ligand backbone had remarkable effects on the activity and enantioselectivity. Replacing the tert-butyl substituents with methoxy substituents at the para positions of the biphenyl moieties improved the enantioselectivities. We have also studied the solution structures of HRh(PP)(CO)(2) complexes. (C) 2001 Elsevier Science Ltd. All rights reserved.
Asymmetric Rh-catalyzed hydrogenation using a furanoside phosphite–phosphoroamidite and diphosphoroamidite ligand library
作者:Mercedes Coll、Oscar Pàmies、Montserrat Diéguez
DOI:10.1039/c2dt11888b
日期:——
A furanoside phosphite–phosphoroamidite and diphosphoroamidite ligand library L1–L5a–f was tested in the asymmetricRh-catalyzedhydrogenation of α,β-unsaturated carboxylic acid derivatives and enamides. Enantioselectivity depended strongly on the ligand parameters. High enantioselectivities were obtained in the reduction of dimethyl itaconate (up to >99% ee), α-dehydroamino acid esters (up to 99%
Modular Furanoside Phosphite-Phosphoroamidites, a Readily Available Ligand Library for Asymmetric Palladium-Catalyzed Allylic Substitution Reactions. Origin of Enantioselectivity
作者:Eva Raluy、Oscar Pàmies、Montserrat Diéguez
DOI:10.1002/adsc.200900073
日期:2009.7
A library of furanoside phosphite‐phosphoroamidite ligands has been synthesized and screened in the palladium‐catalyzed allylicsubstitutionreactions of several substrate types. These series of ligands can be prepared efficiently from easily accessible D‐xylose and D‐glucose. Their modular nature enables the position of the phosphoroamidite group, configuration of C‐3 of the furanoside backbone and