Copper-catalyzed enantioselective synthesis of bridged bicyclic ketals from 1,1-disubstituted-4-methylene-1,6-hexanediols and related alkenols
作者:Ameya S. Burde、Shuklendu D. Karyakarte、Eric D. Sylvester、Sherry R. Chemler
DOI:10.1039/d0cc06404a
日期:——
Bridged bicyclic ketals display a range of bioactivities. Their catalytic enantioselective synthesis from acyclic 1,1-disubstituted alkene diols is disclosed. This reaction combines asymmetric catalysis with a distal radical migration. Alkynes and arenes undergo the group transfer.
Gold nanoclusters stabilized by poly(N-vinyl-2-pyrrolidone) (Au:PVP NCs, O = 1.3nm) behave as Lewis acid catalyst in aqueous media under aerobic conditions, to promote the intramolecular hydroalkoxylation of unactivated alkenes. Molecular oxygen generates a reaction center having the Lewis acidic character on the surface of Au NCs in which constituent gold atoms are formally in zero-valence state.
由聚(N-乙烯基-2-吡咯烷酮)(Au:PVP NCs,O = 1.3nm)稳定的金纳米团簇在有氧条件下在水性介质中充当路易斯酸催化剂,以促进未活化烯烃的分子内加氢烷氧基化。分子氧在 Au NCs 表面产生具有路易斯酸性特征的反应中心,其中组成金原子在形式上处于零价态。
Copper-Catalyzed Enantioselective Aerobic Alkene Aminooxygenation and Dioxygenation: Access to 2-Formyl Saturated Heterocycles and Unnatural Proline Derivatives
作者:Raul L. L. Carmo、Samuel L. Galster、Tomasz Wdowik、Chaeeon Song、Sherry R. Chemler
DOI:10.1021/jacs.3c01985
日期:2023.6.28
Alkeneaminooxygenation and dioxygenation reactions that result in carbonyl products are uncommon, and protocols that control absolute stereochemistry are rare. We report herein catalytic enantioselective alkeneaminooxygenation and dioxygenation that directly provide enantioenriched 2-formyl saturated heterocycles under aerobic conditions. Cyclization of substituted 4-pentenylsulfonamides, catalyzed
Development of Enantioselective Palladium‐Catalyzed Alkene Carboalkoxylation Reactions for the Synthesis of Tetrahydrofurans
作者:Brett A. Hopkins、Zachary J. Garlets、John P. Wolfe
DOI:10.1002/anie.201506884
日期:2015.11.2
The Pd‐catalyzed coupling of γ‐hydroxyalkenes with aryl bromides affords enantiomerically enriched 2‐(arylmethyl)tetrahydrofuran derivatives in good yield and up to 96:4 e.r. This transformation was achieved through the development of a new TADDOL/2‐arylcyclohexanol‐derived chiral phosphite ligand. The transformations are effective with an array of different aryl bromides, and can be used for the preparation
Intramolecular Addition of Toluenesulfonamide to Unactivated Alkenes Catalyzed by Gold Nanoclusters under Aerobic Conditions
作者:Hiroaki Kitahara、Ikuyo Kamiya、Hidehiro Sakurai
DOI:10.1246/cl.2009.908
日期:2009.9.5
Gold nanoclusters stabilized by a hydrophilic polymer, poly(N-vinyl-2-pyrrolidone) (Au:PVP), catalyzed the intramolecular addition of toluenesulfonamide to unactivated alkenes in EtOH under aerobic conditions.