Synthesis of planar chiral [2.2]paracyclophane-based amino thioureas and their application in asymmetric aldol reactions of ketones with isatins
作者:Yu Lu、Yudao Ma、Shaobo Yang、Manyuan Ma、Hongju Chu、Chun Song
DOI:10.1016/j.tetasy.2013.07.023
日期:2013.9
were used as bifunctionalcatalysts for organocatalytic enantioselective aldolreactions between ketones and isatins, affording the desired adducts containing a chiral tertiary alcohol in high yields (up to 92% yield) and with good enantioselectivity (up to 88% ee). This is a successful example of employing planar chiral [2.2]paracyclophane-based amino thioureas in asymmetricaldolreactions.
Enantioselective organocatalytic aldol reaction of unactivated ketones with isatins
作者:Suresh Allu、Nagaraju Molleti、Ramachandrarao Panem、Vinod K. Singh
DOI:10.1016/j.tetlet.2011.05.013
日期:2011.8
Enantioselectiveorganocatalytic direct aldol reaction of unactivated ketones with various isatin derivatives was developed using cinchonine based urea ligand employing a noncovalent catalysis mechanism. Using this protocol we can access functionalized 3-alkyl-3-hydroxyindolin-2-ones in high yields with good to excellent enantioselectivities.
Enantioselective Construction of 3-Hydroxy Oxindoles via Decarboxylative Addition of β-Ketoacids to Isatins
作者:Fangrui Zhong、Weijun Yao、Xiaowei Dou、Yixin Lu
DOI:10.1021/ol301855w
日期:2012.8.3
The first highlyenantioselectivedecarboxylativeaddition of β-ketoacids to isatins mediated by a bifunctional tertiary amine–thiourea catalyst has been developed, allowing facile synthesis of biologically important 3-hydroxyoxindoles in good yields and excellent enantioselectivities. The method reported represents a valuable approach of utilizing β-ketoacids as synthetic equivalents of aryl/alkyl
Enantioselective synthesis of 3-hydroxy oxindoles by ytterbium-catalysed decarboxylative addition of β-ketoacids to isatins
作者:Zhiqiang Duan、Jianlin Han、Ping Qian、Zirui Zhang、Yi Wang、Yi Pan
DOI:10.1039/c3ob41460d
日期:——
A ytterbium(III)-indapybox catalysed enantioselective decarboxylative addition reaction of β-ketoacids to isatins is described. The biologically important 3-hydroxy oxindoles were obtained in high yields and excellent enantioselectivities.
Enantioselective aldol reactions of isatins with acetone using phthalimido-prolinamide organocatalyst 1 are described. The protocol was effective under solvent free and additive free reaction conditions with 20 mol % of 1 leading to the desired aldol products in good yields and with good enantioselectivities. (C) 2015 Elsevier Ltd. All rights reserved.