Enantioselective Catalytic Conjugate Addition of Dialkylzinc Reagents using Copper–Phosphoramidite Complexes; Ligand Variation and Non-linear Effects
作者:Leggy A Arnold、Rosalinde Imbos、Alessandro Mandoli、André H.M de Vries、Robert Naasz、Ben L Feringa
DOI:10.1016/s0040-4020(00)00142-3
日期:2000.4
cyclohexenone and chalcone in order to assess the structural features that are important for stereocontrol. A sterically demanding amine moiety is essential to reach high e.e.’s. Enantioselectivities for chalcones up to 89% and for cyclic enones up to 98% were found. Studies on non-linear effects with the best ligands for both cyclohexenone and chalcone showed clear non-linear effects for both cyclic
METHOD FOR HYDROFORMYLATION OF UNSATURATED COMPOUNDS
申请人:Franke Robert
公开号:US20140024860A1
公开(公告)日:2014-01-23
The invention relates to a method for hydroformylation of unsaturated compounds such as olefins and alkynes using mixtures of synthesis gas (CO/H
2
), in which either the unsaturated compounds and a catalyst are heated to a reaction temperature of 60 to 200° C. and the synthesis gas is then added, or the unsaturated compounds and the catalyst are brought into contact with pure CO at normal temperature in a preformation step, then are heated to reaction temperature and on reaching the reaction temperature the CO is replaced by the synthesis gas. The pressure is 1 to 200 bar and the CO:H
2
ratio in the synthesis gas is in the range from 1:1 to 50:1. The iridium catalyst used comprises a phosphorus-containing ligand in the iridium:ligand ratio in the range from 1:1 to 1:100. With high catalyst activities and low catalyst use, very high turnover frequencies are achieved.
The highly efficient and direct asymmetric reductive amination of arylacetones catalyzed by an iridium complex for the preparation of enantiomerically pure β‐arylamines is described. The monodentate phosphoramidite ligand exhibits superb reactivity (TONs of up to 20 000) and enantioselectivity (up to 99 % ee). Additives played important roles in this reductive coupling reaction.
[EN] SYNTHESIS OF CHROMANE COMPOUNDS AND THEIR DERIVATIVES BY A COPPER-CATALYZED CONJUGATE ADDITION REACTION<br/>[FR] SYNTHÈSE DE COMPOSÉS DE CHROMANE ET DE LEURS DÉRIVÉS PAR UNE RÉACTION D'ADDITION CONJUGUÉE CATALYSÉE PAR DU CUIVRE
申请人:DSM IP ASSETS BV
公开号:WO2015059129A1
公开(公告)日:2015-04-30
The present invention relates to the preparation of chromane compounds and their derivatives by a copper-catalyzed conjugate addition reaction. It has been observed that in highly stereoselective manner a methyl group can be introduced to the 2 position of chromane ring by reaction of a chromenone with Al(CH3)3 in the presence of a Cu(I) salt and specific chiral phosphoramidites. The compounds obtained are important intermediates particularly for the synthesis of chiral tocopherols.
Synthesis and application in asymmetric C–C bond formation of solution phase ligand libraries of monodentate phosphoramidites
作者:Ate Duursma、Laurent Lefort、Jeroen A. F. Boogers、André H. M. de Vries、Johannes G. de Vries、Adriaan J. Minnaard、Ben L. Feringa
DOI:10.1039/b404996a
日期:——
A library of 96 unique monodentate phosphoramidite ligands has been synthesized in solution and used in the asymmetric conjugate addition of potassium vinyltrifluoroborate to enones resulting in up to 88% ee.