Kinetic Resolution of Tertiary Alcohols: Highly Enantioselective Access to 3-Hydroxy-3-Substituted Oxindoles
作者:Shenci Lu、Si Bei Poh、Woon-Yew Siau、Yu Zhao
DOI:10.1002/anie.201209043
日期:2013.2.4
Enantioselective: The first highlyenantioselectivekineticresolution of 3‐hydroxy‐3‐substituted oxindoles has been developed through oxidative esterification catalyzed by a N‐heterocyclic carbene (see picture). This method uses a simple procedure and provides 3‐hydroxy‐oxindoles with various substituents at the 3‐position in excellent enantiopurity. S=selectivity.
The Importance of 1,5‐Oxygen⋅⋅⋅Chalcogen Interactions in Enantioselective Isochalcogenourea Catalysis
作者:Claire M. Young、Alex Elmi、Dominic J. Pascoe、Rylie K. Morris、Calum McLaughlin、Andrew M. Woods、Aileen B. Frost、Alix Houpliere、Kenneth B. Ling、Terry K. Smith、Alexandra M. Z. Slawin、Patrick H. Willoughby、Scott L. Cockroft、Andrew D. Smith
DOI:10.1002/anie.201914421
日期:2020.2.24
5-O⋅⋅⋅chalcogen (Ch) interactions in isochalcogenourea catalysis (Ch=O, S, Se) is investigated. Conformational analyses of N-acyl isochalcogenouronium species and comparison with kinetic data demonstrate the significance of 1,5-O⋅⋅⋅Ch interactions in enantioselective catalysis. Importantly, the selenium analogue demonstrates enhanced rate and selectivity profiles across a range of reaction processes including
A Ni-catalyzed addition of arylboronic acids to isatins was first developed. The reaction, driven by Ni(acac)2 and dppp as the phosphine ligand, gave 3-aryl-3-hydroxy-2-oxindoles in up to 97% yield. Scopes of benzyl-protected isatins and arylboronic acids were examined. Substituted phenylboronic acids along with fused-ring and heterocyclic boronic acids reacted with isatins smoothly. Preliminary asymmetric
A Facile Pathway to Enantiomerically Enriched 3-Hydroxy-2-Oxindoles: Asymmetric Intramolecular Arylation of α-Keto Amides Catalyzed by a Palladium-DifluorPhos Complex
作者:Liang Yin、Motomu Kanai、Masakatsu Shibasaki
DOI:10.1002/anie.201102158
日期:2011.8.8
Less metal wastes: The first catalytic, enantioselective intramolecular aryl‐transfer reaction of aryl triflates to ketones has been developed (see scheme; R1=R2=aromatic and aliphatic). This method features overall practicality, including substrate stability and accessibility (protecting‐group free) plus no need for the use of stoichiometric amounts of metals.
减少金属废料:已开发出芳基三氟甲磺酸酯向酮的第一个催化,对映选择性分子内芳基转移反应(参见方案; R 1 = R 2 =芳族和脂族)。该方法具有整体实用性,包括基材稳定性和可及性(无保护基团),而且无需使用化学计量的金属。