Enantioselective Synthesis of Bicyclopentane-Containing Alcohols via Asymmetric Transfer Hydrogenation
作者:Vijyesh K. Vyas、Guy J. Clarkson、Martin Wills
DOI:10.1021/acs.orglett.1c00889
日期:2021.4.16
1.1]pentane (BCP) adjacent to a chiral center can be prepared with high enantiomeric excess through asymmetrictransferhydrogenation (ATH) of adjacent ketones. In the reduction step, the BCP occupies the position distant from the η6-arene of the catalyst. The reduction was applied to the synthesis of a BCP analogue of the antihistamine drug neobenodine.
conditions, with enantiomeric excesses of up to 96% observed. Kinetic and competition experiments revealed that self-inclusion of the Rh complex contributes to the high enantioselectivity and reactivity achieved by this catalytic system. Thus, this bio-inspired self-inclusion strategy is promising for the development of highly enantioselective and reactive transition-metal catalysts for asymmetric carbon–carbon
Ag-Catalyzed Stereoselective Cyclohexadienyl Transfer: A Novel Entry into Arylphenylmethanols
作者:Rui Umeda、Armido Studer
DOI:10.1021/ol703080a
日期:2008.3.1
The letter describes a novel concept for the synthesis of biologically important arylphenylmethanols. Stereoselective cyclohexadienyl transfer from 1,4-cyclohexadienyltributyltin to various aromatic aldehydes using AgOTf/BINAP as a catalyst precursor provides 1,4-cyclohexadienylphenylmethanols that are readily oxidized to the corresponding arylphenylmethanols. Fifteen examples are presented.
Chelating alkoxy NHC–Rh(I) complexes and their applications in the arylation of aldehydes
In this study, new rhodium(I) complexes (5 and 6) have been prepared by the reaction of [RhCI(COD)](2) with a series of imidazolium salts (3 and 4), which were obtained from a chiral amino alcohol. The catalytic activities of these complexes were tested in the arylation of aldehydes. It was found that the synthesized rhodium complexes were highly effective catalysts for the arylation of aldehydes in short reaction times (5 mm, TOF = 1193 h(-1)). However, the obtained ee values (up to 32% ee) remained low. We have proposed a mechanism for the arylation reaction of aldehydes, which is confirmed via F-19 NMR spectroscopy. (C) 2014 Elsevier Ltd. All rights reserved.
Novel Axially Chiral Phosphine Ligand with a Fluoro Alcohol Moiety for Rh-Catalyzed Asymmetric Arylation of Aromatic Aldehydes
作者:Satoshi Morikawa、Kyosuke Michigami、Hideki Amii
DOI:10.1021/ol100697a
日期:2010.6.4
A new chiral phosphine ligand (R)-1 possessing a fluoroalcohol moiety was prepared. The (R)-1-coordinated Rh(I) complex showed an excellent catalytic activity for asymmetric 1,2-addition of arylboronic acids to aldehydes to afford highly enantioenriched diarylmethanols. The fluoroalcohol moiety in ligand (R)-1 plays a pivotal role for the high enantioselectivity of the present Rh(I)-catalyzed transformation.