Discovery of Annulating Reagents Enabling the One-Step and Highly Stereoselective Synthesis of Cyclopentyl and Cyclohexyl Cores
作者:Jade McDaniel、Christopher A. Farley、Antonio Ramirez、Bhupinder Sandhu、Amy Sarjeant、Qing Shi、Arthur Han、William P. Gallagher、John Hynes、T. G. Murali Dhar、Francisco Gonzalez-Bobes、John R. Coombs、David Marcoux
DOI:10.1021/acs.orglett.0c03695
日期:2021.1.1
undergo cycloaddition with a variety of Michael acceptors to form cyclopentane/cyclohexane rings with excellent stereochemicalcontrol, generating only one of the eight possible diastereomers. This novel methodology has enabled the highly enantioselective and high yielding synthesis of novel chemotypes of pharmacological relevance.
Application of <i>P,N-</i>Sulfinyl Imine Ligands to Iridium-Catalyzed Asymmetric Hydrogenation of Olefins
作者:Laurie B. Schenkel、Jonathan A. Ellman
DOI:10.1021/jo035675+
日期:2004.3.1
The utility of a novel class of P,N-ligands incorporating a chiral sulfinyl imine moiety is demonstrated in the iridium-catalyzedhydrogenation of both functionalized and unfunctionalized olefins, in which enantioselectivities of up to 94% are achieved. The modularity of the P,N-sulfinyl ligand class is highlighted by the facile preparation of a variety of sterically and electronically different ligands
Development of an N-sulfinyl prolinamide for the asymmetric aldol reaction
作者:MaryAnn T. Robak、Melissa A. Herbage、Jonathan A. Ellman
DOI:10.1016/j.tet.2011.03.030
日期:2011.6
reported that incorporates an N-sulfinyl amide in place of the carboxylic acid of proline to serve as a hydrogen bond donor, chiral directing group, and solubilizing element. The successful application of this type of catalyst to the asymmetricaldolreaction of acetone and aryl aldehydes, for which proline performs poorly, is also described.
Catalytic Enantioselective Addition of Pyrazol-5-ones to Trisubstituted Nitroalkenes with an <i>N</i>
-Sulfinylurea Organocatalyst
作者:James P. Phelan、Jonathan A. Ellman
DOI:10.1002/adsc.201600110
日期:2016.6.2
The first example of enantioselective nitronate protonation following Michaeladdition of a carbon nucleophile to an α,β,β‐trisubstituted nitroalkene is reported. An N‐sulfinylurea catalyst was employed to catalyze the addition of a variety of 3‐substituted pyrazol‐5‐one nucleophiles to trisubstituted nitroalkenes incorporating an oxetane or azetidine ring at the β‐position. The nitroalkane‐pyrazolone
Enantio- and diastereoselective addition of thioacetic acid to nitroalkenes via N-sulfinyl urea catalysis
作者:Kyle L. Kimmel、MaryAnn T. Robak、Stephen Thomas、Melissa Lee、Jonathan A. Ellman
DOI:10.1016/j.tet.2012.01.048
日期:2012.3
The enantioselective addition of thioacetic acid to nitroalkenes was achieved using N-sulfinyl urea catalysis. In this report, the scope of the reaction was extended to the enantio- and diastereoselective thioacetic acid addition to cyclic alpha,beta-disubstituted nitroalkenes. Additionally, the role of the sulfinyl group was investigated by replacing it with a variety of aryl and sulfonyl groups. Of 15 urea catalysts synthesized and tested, none displayed comparable selectivity to the sulfinyl catalysts, highlighting the importance of the sulfinyl group in attaining high enantioselectivity in the thioacetic acid addition. (C) 2012 Elsevier Ltd. All rights reserved.