Enantioselective Ruthenium(II)/Xyl-SunPhos/Daipen-Catalyzed Hydrogenation of γ-Ketoamides
摘要:
A series of gamma-hydroxy amides were synthesized with high enantioselectivities (up to 99%) using asymmetric hydrogenation of the corresponding gamma-ketoamides in the presence of Ru-Xyl-SunPhos-Daipen catalyst providing key building blocks for a variety of naturally occurring and biologically active compounds.
Quaternary Charge-Transfer Complex Enables Photoenzymatic Intermolecular Hydroalkylation of Olefins
作者:Claire G. Page、Simon J. Cooper、Jacob S. DeHovitz、Daniel G. Oblinsky、Kyle F. Biegasiewicz、Alyssa H. Antropow、Kurt W. Armbrust、J. Michael Ellis、Lawrence G. Hamann、Evan J. Horn、Kevin M. Oberg、Gregory D. Scholes、Todd K. Hyster
DOI:10.1021/jacs.0c11462
日期:2021.1.13
Intermolecular C-C bond-formingreactions are underdeveloped transformations in the field of biocatalysis. Here we report a photoenzymatic intermolecular hydroalkylation of olefins catalyzed by flavin-dependent 'ene'-reductases. Radical initiation occurs via photoexcitation of a rare high-order enzyme-templated charge-transfer complex that forms between an alkene, α-chloroamide, and flavin hydroquinone
[structure: see text]. A cationic rhodium(I)/dppb complex catalyzed direct intermolecular hydroacylation of N,N-dialkylacrylamides with both aliphatic and aromatic aldehydes has been achieved through the stabilization of acylrhodium intermediates by alkene chelation to rhodium. This method represents a versatile new route to gamma-ketoamides in view of the high atom economy and commercial availability
Decarboxylative 1,4-Addition of α-Oxocarboxylic Acids with Michael Acceptors Enabled by Photoredox Catalysis
作者:Guang-Zu Wang、Rui Shang、Wan-Min Cheng、Yao Fu
DOI:10.1021/acs.orglett.5b02392
日期:2015.10.2
Enabled by iridium photoredoxcatalysis, 2-oxo-2-(hetero)arylacetic acids were decarboxylatively added to various Michael acceptors including α,β-unsaturated ester, ketone, amide, aldehyde, nitrile, and sulfone at room temperature. The reaction presents a new type of acyl Michael addition using stable and easily accessible carboxylicacid to formally generate acyl anion through photoredox-catalyzed
Generation of α-Radicals of Acetic Acid Derivatives from α-Stannyl Ester and Amide and Their Reactions with Electron-Rich Olefins
作者:Yasushi Kohno、Koichi Narasaka
DOI:10.1246/cl.1993.1689
日期:1993.10
Oxidation of α-tributylstannyl ester and amide with CeIV compounds generates α-radicals of acetic acidderivatives with the elimination of the stannyl group. The radicals thus generated react with various electron-rich olefins to give the corresponding addition products in good yield.
Eco-Friendly Syntheses of 2-Substituted Benzoxazoles and 2-Substituted Benzothiazoles from 2-Aminophenols, 2-Aminothiophenols and DMF Derivatives in the Presence of Imidazolium Chloride
A simple, economical and metal-free approach to the synthesis of 2-substituted benzoxazoles and 2-substituted benzothiazoles from 2-aminophenols, 2-aminothiophenols and DMF derivatives, only using imidazolium chloride (50% mmol) as promoter without any other additive, was reported. Various 2-substituted benzoxazoles and 2-substituted benzothiazoles were thus prepared in moderate to excellent yields