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.
Kinetic Resolution of Tertiary Alcohols by Chiral DMAP Derivatives: Enantioselective Access to 3-Hydroxy-3-substituted 2-Oxindoles
作者:Hiroki Mandai、Ryuhei Shiomoto、Kazuki Fujii、Koichi Mitsudo、Seiji Suga
DOI:10.1021/acs.orglett.0c03956
日期:2021.2.19
We developed an efficient acylative kineticresolution of 3-hydroxy-3-substituted 2-oxindoles by a chiral DMAP derivative having a 1,1′-binaphthyl with two tert-alcohols units. A wide range of 3-hydroxy-3-substitutedoxindoles having various functional groups were efficiently resolved (14 examples, up to s = 60) in the presence of 1 mol % of catalyst within 3–9 h. Multigram-scale reactions (10 g) also
Chiral CNN Pincer Palladium(II) Complexes with 2-Aryl-6-(oxazolinyl)pyridine Ligands: Synthesis, Characterization, and Application to Enantioselective Allylation of Isatins and Suzuki–Miyaura Coupling Reaction
作者:Tao Wang、Xin-Qi Hao、Juan-Juan Huang、Kai Wang、Jun-Fang Gong、Mao-Ping Song
DOI:10.1021/om400945d
日期:2014.1.13
1-naphthyl) ligands 2a–f were conveniently prepared from commercially available 6-bromo-2-picolinaldehyde in two steps. Reaction of 2a–f with PdCl2 in toluene in the presence of sodium bicarbonate afforded the corresponding CNNpincer Pd(II) complexes 3a–f via aryl C–H bond activation of the related ligands. All of the new compounds have been fully characterized by elemental analysis (MS for ligands), 1H
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