Results 31 to 40 of about 32,089 (279)
Organocatalyzed Enantioselective Fluorocyclizations
Angewandte Chemie International Edition, 2011 Enantioenriched fluorinated heterocycles can be prepared through fluorocyclizations of prochiral indoles (see scheme; Ts=tosyl, Bn=benzyl, Boc=tert-butoxycarbonyl). More than twenty examples for this cascade fluorination-cyclization, which is catalyzed by cinchona alkaloids and employs N-fluorobenzenesulfonimide as the electrophilic fluorine source ...
Lozano, O +8 more
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Homochiral Metal-Organic Framework Based Mixed Matrix Membrane for Chiral Resolution
Membranes, 2022 Efficient separation of enantiomers is critical in the chemical, pharmaceutical, and food industries. However, conventional separation methods, such as chromatography, crystallization, and enzymatic kinetic resolution, require high energy costs and ...
Hwa-Jin Choi, Dong-Yeun Koh
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Palladium and copper-catalysed (C-C)-bond formation [PDF]
, 2006 Copper-Catalysed Conjugate Additions: Conjugate 1,4-additions of carbon nucleophiles to α,β-unsaturated ketones are valuable C-C bond forming reactions that furthermore allow introduction of stereogenic centers.(1) Copper-catalysed reactions have been ...
Bulic, Bruno
core +1 more source
Synthetic Cathinones: Recent Developments, Enantioselectivity Studies and Enantioseparation Methods
Molecules, 2022 New psychoactive substances represent a public health threat since they are not controlled by international conventions, are easily accessible online and are sold as a legal alternative to illicit drugs. Among them, synthetic cathinones are widely abused
Ana Sofia Almeida +4 more
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Carbohydrate-Based Azacrown Ethers in Asymmetric Syntheses
Chemistry, 2021 Carbohydrate-based crown ethers represent a special group of chiral phase transfer catalysts. Several derivatives of these macrocycles have been synthesized in our research group.
István Orbán, Péter Bakó, Zsolt Rapi
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Molecules, 2023 Synthetic cathinones, such as 3,4-methylenedioxypyrovalerone (MDPV), are widely abused due to their psychostimulant effects. As they are chiral molecules, studies of their stereochemical stability (racemization can occur in certain temperatures and ...
Ana Sofia Almeida +5 more
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Enhanced Production of (S)-2-arylpropionic Acids by Protein Engineering and Whole-Cell Catalysis
Frontiers in Bioengineering and Biotechnology, 2021 Esterases are important biocatalysts for chemical synthesis. Several bHSL family esterases have been used to prepare (S)-2-arylpropionic acids with stronger anti-inflammatory effects via kinetic resolution.
Xiaolong Liu +3 more
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Enantioselective Desymmetrization of FTY720
Chemical and Pharmaceutical Bulletin, 2014 A method for enantioselective desymmetrization of N-Ac and N-Boc-FTY720 by nonenzymatic asymmetric acylation was developed. Effective enantioselective monobenzoylation using benzoyl chloride in the presence of the tetraphenylbisoxazoline (L2)-CuCl2 complex gave the desired products 3a and 3b in 52-62% yield with 64% ee.
Hikawa, Hidemasa +5 more
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Enantioselective synthesis of (−)-paeonilide [PDF]
Chemical Communications, 2012 The first enantioselective synthesis of (−)-paeonilide is reported. Starting from inexpensive furan-3-carboxylic acid the targeted monoterpene was obtained in 12 steps via an asymmetric cyclopropanation-lactonization cascade and a stereoselective side chain insertion at an acetal-like position.
Klaus, Harrar, Oliver, Reiser
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Enantioselective Hydrocarbamoylation of Alkenes
Angewandte Chemie International Edition, 2022 AbstractThe asymmetric hydroaminocarbonylation of olefins represents a straightforward approach for the synthesis of enantioenriched amides, but is hampered by the necessity to employ CO gas, often at elevated pressures. We herein describe, as an alternative, an enantioselective hydrocarbamoylation of alkenes leveraging dual copper hydride and ...
Sheng Feng +2 more
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