A C=O⋅⋅⋅Isothiouronium Interaction Dictates Enantiodiscrimination in Acylative Kinetic Resolutions of Tertiary Heterocyclic Alcohols
作者:Mark D. Greenhalgh、Samuel M. Smith、Daniel M. Walden、James E. Taylor、Zamira Brice、Emily R. T. Robinson、Charlene Fallan、David B. Cordes、Alexandra M. Z. Slawin、H. Camille Richardson、Markas A. Grove、Paul Ha‐Yeon Cheong、Andrew D. Smith
DOI:10.1002/anie.201712456
日期:2018.3.12
C=O⋅⋅⋅isothiouronium interaction as key to efficient enantiodiscrimination in the kineticresolution of tertiary heterocyclic alcohols bearing up to three potential recognition motifs at the stereogenic tertiary carbinol center. This discrimination was exploited in the isothiourea‐catalyzed acylative kineticresolution of tertiary heterocyclic alcohols (38 examples, s factors up to >200). The reaction proceeds at low
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。