Abstract Disclosed herein is a photochemical organocatalytic strategy for the direct enantioselective Mannich-type reaction of 2-alkylbenzophenones and cyclicimines. The chemistry exploits the light-triggered enolization of 2-alkylbenzophenones to generate transient hydroxy-o-quinodimethanes. These fleeting intermediates can be stereoselectively intercepted by imines upon activation with a chiral organic
A Chiral Nitrogen Ligand for Enantioselective, Iridium-Catalyzed Silylation of Aromatic C−H Bonds
作者:Bo Su、Tai-Gang Zhou、Xian-Wei Li、Xiao-Ru Shao、Pei-Lin Xu、Wen-Lian Wu、John F. Hartwig、Zhang-Jie Shi
DOI:10.1002/anie.201609939
日期:2017.1.19
containing dative nitrogen ligands are highly active for the borylation and silylation of C−Hbonds, but chiral analogs of these catalysts for enantioselective silylation reactions have not been developed. We report a new chiral pyridinyloxazoline ligand for enantioselective, intramolecular silylation of symmetrical diarylmethoxy diethylsilanes. Regioselective and enantioselective silylation of unsymmetrical
Propionic Acid Derivatives and Methods of Use Thereof
申请人:Biediger Ronald J.
公开号:US20180312498A1
公开(公告)日:2018-11-01
Provided herein are compounds and pharmaceutical compositions of formula I
where R
1
, R
2
, R
3
, R
4
, R
5
, X and R
6
are as described herein. Also provided pharmaceutically acceptable salts or stereoisomer(s) of these compounds. In addition methods are provided for antagonizing the action of an α4-integrin to treat various pathophysiological conditions.
A light-driven, catalyst- and additive-free photoenolization/nucleophilic addition reaction for the synthesis of 3-benzyl-3-hydroxyindolin-2-ones is presented. In this reaction, 2-methylbenzophenones undergo light-induced enolization process to afford hydroxy-o-quinodimethanes (hydroxy-o-QDMs), which are then immediately captured by the electrophilic isatins. The reaction utilizes green and clean light