Homogeneous Gold-Catalyzed Oxidation Reactions

Chemical Reviews, Год журнала: 2021, Номер 121(14), С. 8979 - 9038

Опубликована: Фев. 16, 2021

Homogeneous gold catalysis has experienced extraordinary development since the dawn of this millennium. Oxidative is a vibrant and fertile subfield over years delivered diverse array versatile synthetic methods exceptional value to practices. This review aims cover topic in comprehensive manner. The discussions are organized by mechanistic aspects metal oxidation states further types oxidants or oxidizing functional groups. Synthetic applications oxidative also discussed.

Язык: Английский

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Enantioselective Oxidative Multi-Functionalization of Terminal Alkynes with Nitrones and Alcohols for Expeditious Assembly of Chiral α-Alkoxy-β-amino-ketones

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(36), С. 14703 - 14711

Опубликована: Авг. 31, 2021

Catalytic oxidative functionalization of alkynes has emerged as an effective method in synthetic chemistry recent decades. However, enantioselective transformations via metal carbene intermediates are quite rare due to the lack robust chiral catalysts, especially intermolecular versions. Herein, we report first asymmetric three-component reaction commercially available with nitrones and alcohols, which affords α-alkoxy-β-amino-ketones good yields high excellent enantioselectivity using combined catalysis by achiral gold complex a spiro phosphoric acid (CPA). Mechanistically, this atom-economic involves catalytic alkyne oxidation/ylide formation/Mannich-type addition sequence that uses nitrone oxidant leaving fragment imine electrophile, providing novel for multi-functionalization terminal alkynes.

Язык: Английский

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Gold-catalyzed multicomponent reactions

Organic Chemistry Frontiers, Год журнала: 2023, Номер 10(9), С. 2359 - 2384

Опубликована: Янв. 1, 2023

Multicomponent reactions (MCRs) have emerged as an important branch in organic synthesis for the creation of complex molecular structures. This review is focused on gold-catalyzed MCRs with a special emphasis recent developments.

Язык: Английский

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Photocatalytic functionalizations of alkynes

Chemical Communications, Год журнала: 2021, Номер 57(86), С. 11285 - 11300

Опубликована: Янв. 1, 2021

Visible light mediated functionalizations have significantly expanded the scope of alkynes by unraveling new mechanistic pathways and enabling their transformation to diverse structural entities. The photoredox reactions on rely innate capability generate myriad carbon-centred radicals via single electron transfer (SET), thereby, allowing introduction radical precursors. Moreover, an array methods been developed facilitating transformations such as vicinal or gem-difunctionalization, annulation, cycloaddition oxidative construct numerous key building blocks natural pharmaceutically important molecules. In addition, chemistry has successfully used deal with challenges associated alkyne functionalization stereoselective regioselective control. This article accounts for several visible alkynes, wherein they transformed into α-oxo compounds, β-keto sulfoxides, substituted olefins, N-heterocycles, internal sulfur containing compounds. primarily categorized various sections based reaction type particular attention being paid details, advancement future applications.

Язык: Английский

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Asymmetric Three-Component Reaction of Enynal with Alcohol and Imine as An Expeditious Track to Afford Chiral α-Furyl-β-amino Carboxylate Derivatives

ACS Catalysis, Год журнала: 2022, Номер 12(22), С. 14185 - 14193

Опубликована: Ноя. 4, 2022

Herein, we report an achiral dirhodium complex and chiral phosphoric acid cooperatively catalyzed asymmetric three-component reaction of enynal with alcohol imine, affording α-furyl-β-amino carboxylates in good to high yields generally excellent stereoselectivity. The successful introduction as a carbene precursor this provides expeditious track prepare furan derivatives adjacent quaternary tertiary stereocenters. starting materials are stable readily available, the method features 100% atom economy bond-formation efficiency. This is highly enantioselective gem-difunctionalization metal generated situ from enynal. These products could be smoothly converted polycyclic frameworks drug-conjugated through different cycloaddition reactions.

Язык: Английский

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Energy Transfer (EnT)-Mediated Stereoselective Aryl-Heterofunctionalization of Unactivated Alkynes via Radical Rearrangement

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 5, 2025

In this study, we present a novel catalyst-free energy transfer mediated radical rearrangement strategy for the aryl-heterofunctionalization of unactivated alkynes, leading to synthesis polyfunctional olefins with exceptional stereoselectivity. This innovative approach, driven by visible light, exemplifies green chemistry principles eliminating reliance on transition metals, external oxidants, and photocatalysts. The broad applicability our method is demonstrated through successful diverse array compounds, including vinyl sulfones, selenides, sulfides. Preliminary mechanistic insights suggest an mechanism, highlighting efficiency selectivity strategy.

Язык: Английский

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Gold-Catalyzed Intermolecular Alkyne Hydrofunctionalizations—Mechanistic Insights

Catalysts, Год журнала: 2020, Номер 10(10), С. 1210 - 1210

Опубликована: Окт. 19, 2020

An overview of the current state mechanistic understanding gold-catalyzed intermolecular alkyne hydrofunctionalization reactions is presented. Moving from analysis main features by-now-generally accepted reaction mechanism, studies and evidences pointing out peculiarities these using different nucleophiles HNu that add to triple bond are presented discussed. The effects nature employed substrate gold catalyst (employed ligands, counteranions, oxidation state), additional additives conditions also considered. Aim this work provide reader with a detailed knowledge important class, which will be invaluable for rapidly developing optimizing synthetic protocols involving as step.

Язык: Английский

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Reactivities of α‐Oxo BMIDA Gold Carbenes Generated by Gold‐Catalyzed Oxidation of BMIDA‐Terminated Alkynes

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(17)

Опубликована: Фев. 21, 2023

An oxidative strategy is reported to access α-oxo BMIDA gold carbenes directly from BMIDA-terminated alkynes. Besides offering expedient seldom studied boryl metal carbenes, these carbene species undergo facile insertions into methyl, methylene, methine, and benzylic C-H bonds in the absence of Thorpe-Ingold effect. They also efficient OH insertion, cyclopropanation, F-C alkylations. This chemistry provides rapid structurally diverse α-BMIDA ketones, which are scarcely documented. In combination with DFT studies, role established be an electron-donating group that attenuates high electrophilicity center.

Язык: Английский

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Azido-alkynylation of alkenes through radical-polar crossover

Chemical Science, Год журнала: 2023, Номер 14(35), С. 9452 - 9460

Опубликована: Янв. 1, 2023

We report an azido-alkynylation of alkenes allowing a straightforward access to homopropargylic azides by combining hypervalent iodine reagents and alkynyl-trifluoroborate salts. The design photocatalytic redox-neutral radical polar crossover process was key develop this transformation. A variety possessing electron-rich -poor aryls, heterocycles or ether substituents could be accessed in 34-84% yield. products are synthetically useful building blocks that easily transformed into pyrroles bioactive amines.

Язык: Английский

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Regioselective C−H Functionalization of HeteroareneN‐Oxides Enabled by a Traceless Nucleophile

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(50), С. 22675 - 22683

Опубликована: Сен. 5, 2020

Although N-alkenoxyheteroarenium salts have been widely used as umpoled synthons with nucleophilic (hetero)arenes, the use of electron-poor heteroarenes has remained unexplored. To overcome inherent electron deficiency quinolinium salts, a traceless nucleophile-triggered strategy was designed, wherein segment is converted into dearomatized intermediate, thereby allowing simultaneous C8-functionalization quinolines at room temperature. Experimental and computational studies support operation nucleophile, which enables previously inaccessible transformation salts. Remarkably, generality this further demonstrated by broad applications in regioselective C-H functionalization other electron-deficient such phenanthridine, isoquinoline, pyridine N-oxides, offering practical tool for late-stage complex biorelevant molecules.

Язык: Английский

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