Recent advances in transition-metal-catalyzed carbene insertion to C–H bonds

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(7), P. 2759 - 2852

Published: Jan. 1, 2022

C-H functionalization has been emerging as a powerful method to establish carbon-carbon and carbon-heteroatom bonds. Many efforts have devoted transition-metal-catalyzed direct transformations of Metal carbenes generated in situ from transition-metal compounds diazo or its equivalents are usually applied the transient reactive intermediates furnish catalytic cycle for new C-C C-X bond formation. Using this strategy unactivated simple alkanes complex molecules can be further functionalized transformed multi-functionalized compounds. In area, carbene insertion bonds paid continuous attention. Diverse catalyst design strategies, synthetic methods, potential applications developed. This critical review will summarize advance dated up July 2021, by categories aliphatic C(sp3)-H, aryl (aromatic) C(sp2)-H, heteroaryl (heteroaromatic) C(sp2)-H bonds, alkenyl alkynyl C(sp)-H, well asymmetric more coverage given recent work. Due rapid development future directions topic also discussed. give authors an overview chemistry with focus on systems

Language: Английский

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Asymmetric Catalytic Rearrangements with α-Diazocarbonyl Compounds

Accounts of Chemical Research, Journal Year: 2022, Volume and Issue: 55(3), P. 415 - 428

Published: Jan. 14, 2022

Conspectusα-Diazocarbonyl compounds serve as nucleophiles, dipoles, carbene precursors, and rare electrophiles, enabling a vast array of organic transformations under the influence metal catalysts. Among them, rearrangement processes are attractive provide straightforward efficient accesses to one-carbon extension adducts or heteroatom-containing molecules. The reactions occur upon release dinitrogen after nucleophilic addition before ylide formation. Although significant progress has been made for these two types reactions, issue enantiocontrol is challenging because final optically enriched products generated via multistep inherent spacial arrangement intermediates more less on regio- enantioselectivity.In this Account, we collected several rearrangements α-diazocarbonyl compounds, showcasing catalysts tailored strategies tackling enantioselective varieties reactions. Our research group initiated catalytic asymmetric during development chiral Feng N,N′-dioxide–metal complex others. As kind useful Lewis acid catalyst complexes favorable activation various carbonyl accelerating diastereo- α-diazoesters sequential in either an intermolecular intramolecular manner. Aldehydes, acyclic cyclic ketone derivatives, α,β-unsaturated ketones could participate homologation obvious ligand-acceleration effect observed processes. For example, Roskamp–Feng reaction aldehydes gives active β-ketoesters through H-shift, overwhelming aryl shift oxygen attack. preference derivatives be excellent control An unusual electrophilic α-amination aryl/alkyl even complicated homologation/dyotropic rearrangement/interconversion/[3 + 2] cycloaddition cascade used construct dimeric polycyclic were discovered result selection ligands additives. On basis understanding interaction functional with catalysis key enantio-determining issues ylide-based rearrangements, designed new by introducing pyrazole-1-carboxyl acceptor unit, which benefit formation both carbenoid species catalyst-bound ylides deliver stereoselectivity. Taking advantage Ni(II) Co(II) N,N′-dioxide ligands, realized kinds [2,3]-sigmatropic such Doyle–Kirmse allylic sulfides selenides, [2,3]-Stevens vinyl-substituted α-diazo pyrazoleamides thioacetates, Sommelet–Hauser aryl-substituted thioamides, thio-Claisen 2-thio-indoles well. Moreover, strategy was shown applicable highly γ-selective insertion into N–H bonds secondary amines pyrazoleamides.

Language: Английский

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Unlocking novel reaction pathways of diazoalkanes with visible light

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(17), P. 2788 - 2798

Published: Jan. 1, 2022

In this feature article, the photolysis and dye-sensitized reactions of diazoalkanes are discussed applications in organic synthesis presented.

Language: Английский

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Visible Light-Induced Reactions of Diazo Compounds and Their Precursors

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(11), P. 7214 - 7261

Published: May 16, 2024

In recent years, visible light-induced reactions of diazo compounds have attracted increasing attention in organic synthesis, leading to improvement existing reactions, as well the discovery unprecedented transformations. Thus, photochemical or photocatalytic generation both carbenes and radicals provide milder tools toward these key intermediates for many valuable However, vast majority transformations represent new reactivity modes compounds, which are achieved by decomposition photoredox catalysis. particular, use a redox-active photocatalysts opens avenue plethora radical reactions. The application methods led inaccessible classical associated with metal carbenes. most cases, act sources but can also serve acceptors. Importantly, described processes operate under mild, practical conditions. This Review describes this subfield compound chemistry, particularly focusing on advancements.

Language: Английский

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Visible light-mediated photolysis of organic molecules: the case study of diazo compounds

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(48), P. 7346 - 7360

Published: Jan. 1, 2023

This article discusses the photochemistry of several diazo compounds undergoing visible light-mediated photolysis to generate free carbenes (or other highly reactive intermediates), which can be sequentially trapped by different reacting partners.

Language: Английский

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Advances in heterocycle synthesis through photochemical carbene transfer reactions

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(16), P. 2125 - 2136

Published: Jan. 1, 2024

In this feature article, we focus on the photochemical strategy for construction of heterocyclic skeletons, specifically highlighting methods that employ visible light-promoted carbene transfer reactions.

Language: Английский

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Photocatalytic Activation of Aryl(trifluoromethyl) Diazos to Carbenes for High-Resolution Protein Labeling with Red Light

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(2), P. 1337 - 1345

Published: Jan. 2, 2024

State-of-the-art methods in photoproximity labeling center on the targeted generation and capture of short-lived reactive intermediates to provide a snapshot local protein environments. Diazirines are current gold standard for high-resolution proximity labeling, generating aryl(trifluoromethyl) carbenes. Here, we present method access carbenes from stable diazo source via tissue-penetrable, deep red near-infrared light (600–800 nm). The operative mechanism this activation involves Dexter energy transfer photoexcited osmium(II) photocatalysts diazo, thus revealing an carbene. preferences probe with amino acids studied, showing high reactivity toward heteroatom−H bonds. Upon synthesis biotinylated probe, studies conducted native proteins as well conjugated Os photocatalyst. Finally, demonstrate that conjugation inhibitor photocatalyst also enables selective presence spectator achieves specific membrane surface mammalian cells two-antibody photocatalytic system.

Language: Английский

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Photodriven Radical-Polar Crossover Cyclization Strategy: Synthesis of Pyrazolo[1,5-a]pyridines from Diazo Compounds

Organic Letters, Journal Year: 2024, Volume and Issue: 26(12), P. 2511 - 2516

Published: March 20, 2024

This work demonstrates the synthesis of a variety perfluoroalkyl heterocycles via visible-light-driven radical-polar crossover cyclization strategy. In this process, single-electron reduction/SNV-type/cyclization sequences follow radical addition reaction diazoester, which differs from current role diazoesters as precursors/acceptors. transformation excellent functional group compatibility and allows for modification many bioactive molecules with diazoesters. Such could represent novel approach to photochemical diazo compounds.

Language: Английский

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Visible Light-Promoted Transformation of Diazo Compounds via the Formation of Free Carbene as Key Intermediate

Chinese Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 41(12), P. 4565 - 4565

Published: Jan. 1, 2021

Carbene is one of the most important synthetic intermediates in organic synthesis.In past few decades, transition-metal catalyzed carbene transfer reactions have made remarkable development.Recently, visible light-promoted transformation diazo compounds through formation free as key intermediate begun to rise.The reaction only need light sole energy source which meets concept green chemistry.Since pioneering works developed by groups Diaves and Zhou, photo-promoted has attracted more attentions.On basis previous work, latest progress this field further improved, mainly focuses on recent new under irradiation contributions reported from Chinese research group.The future development direction, well challenges prospected.

Language: Английский

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Photocatalytic gem‐Difluoroolefination Reactions by a Formal C−C Coupling/Defluorination Reaction with Diazoacetates

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 61(4)

Published: Oct. 30, 2021

The photolysis of diazoalkanes to conduct singlet carbene transfer reactions colored has recently attracted significant interest in organic synthesis. Herein, we describe a photocatalytic approach that allows the access triplet intermediates via energy highly efficient gem-difluoroolefination with α-trifluoromethyl styrenes. use tertiary amines proved pivotal unlock this unusual reaction pathway and prevent undesired cyclopropanation pathways. amine further facilitates ultimate abstraction fluoride yield gem-difluoroolefins (43 examples, up 88 % yield), which is supported by experimental theoretical mechanistic studies. We explored synthesis method broad substrate scope, ranging from simple olefins heterocyclic towards decoration pharmaceutically relevant building blocks.

Language: Английский

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