Nickel-Catalyzed Atroposelective C–H Alkylation Enabled by Bimetallic Catalysis with Air-Stable Heteroatom-Substituted Secondary Phosphine Oxide Preligands

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(13), С. 9172 - 9180

Опубликована: Март 21, 2024

The catalytic asymmetric construction of axially chiral C–N atropisomers remains a formidable challenge due to their low rotational barriers and is largely reliant on toxic, cost-intensive, precious metal catalysts. In sharp contrast, we herein describe the first nickel-catalyzed atroposelective C–H alkylation for compounds with aid heteroatom-substituted secondary phosphine oxide (HASPO)-ligated Ni–Al bimetallic catalyst. A wide range alkenes, including terminal internal were well compatible reaction, providing variety benzimidazole derivatives in high yields enantioselectivities (up 97:3 e.r.). key success was identification novel HASPOs as highly effective preligands. Mechanistic studies revealed catalyst mode action, in-depth data science analysis elucidated features responsible preligands controlling enantioselectivity.

Язык: Английский

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Nickel-catalyzed C(sp2)–H alkynylation of free α-substituted benzylamines using a transient directing group

Chinese Chemical Letters, Год журнала: 2025, Номер unknown, С. 110901 - 110901

Опубликована: Янв. 1, 2025

Язык: Английский

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Enantioselective C–H annulations enabled by either nickel- or cobalt-electrocatalysed C–H activation for catalyst-controlled chemodivergence

Nature Catalysis, Год журнала: 2025, Номер unknown

Опубликована: Март 7, 2025

Язык: Английский

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Divergent Transformations of Aromatic Esters: Decarbonylative Coupling, Ester Dance, Aryl Exchange, and Deoxygenative Coupling

Accounts of Chemical Research, Год журнала: 2024, Номер 57(12), С. 1747 - 1760

Опубликована: Май 31, 2024

ConspectusAromatic esters are cost-effective, versatile, and commonly used scaffolds that readily synthesized or encountered as synthetic intermediates. While most conventional reactions involving these nucleophilic acyl substitutions 1,2-nucleophilic additions─where a nucleophile attacks the carbonyl group, decarbonylative transformations offer an alternative pathway by using group leaving group. This transition-metal-catalyzed process typically begins with oxidative addition of C(acyl)–O bond to metal. Subsequently, reaction involves migration CO metal center, nucleophile, reductive elimination yield final product. Pioneering work Yamamoto on nickel complexes development (such Mizoroki–Heck-type olefination) aromatic carboxylic anhydrides catalyzed palladium were conducted de Vries Stephan. Furthermore, reports have surfaced hydrogenation pyridyl methyl Murai ruthenium catalysts well nitro phenyl Gooßen under catalysis. Our has been at forefront developing C–H arylations 1,3-azoles aryl boronic acids catalysts. The key this is use esters, which easy synthesize, stabilize, handle, allowing bond; nickel, facilitates suitable bidentate phosphine ligands can stabilize intermediate. By modification nucleophiles, effectively utilized electrophiles in cross-coupling reactions, encouraging nucleophiles among researchers. Account summarizes our advancements for coupling particularly highlighting utilization diverse such alkenylation, intramolecular etherification, α-arylation ketones, arylation, methylation, arylation dibenzofuran synthesis, along cyanation coupling. We also delve into types distinct from typical including ester dance ring exchanges, deoxygenative transformations, focusing complex. For example, hypothesized undergo 1,2-translocation starting complex, leading sequence ortho-deprotonation/decarbonylation, followed protonation, carbonylation, elimination. exchange likely different In coupling, complex engages forming intermediate undergoes presence appropriate reducing agent. These methodologies poised captivate interest chemists offering unconventional emerging approaches transforming esters. Moreover, we demonstrated potential transform available basic chemicals new compounds through organic synthesis.

Язык: Английский

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Nickel-Catalyzed Lactamization Reaction of 2-Arylanilines with CO₂

Organic Letters, Год журнала: 2024, Номер 26(18), С. 3940 - 3944

Опубликована: Апрель 30, 2024

Transition-metal-catalyzed lactamization and lactonization of C–H bonds with CO2 assisted by the chelation amino or hydroxyl groups have been developed but limited to use precious metal catalysts such as palladium rhodium. In this work, we report nonprecious nickel-catalyzed reaction 2-arylanilines under redox-neutral conditions via bond activation. The displayed excellent functional group tolerance, providing various phenanthridinones moderate high yields.

Язык: Английский

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Mechanistic Investigations of Cobalt-Catalyzed, Aminoquinoline-Directed C(sp²)–H Bond Functionalization

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Янв. 10, 2025

Monoanionic, bidentate-auxiliary-directed, cobalt-catalyzed C–H bond functionalization has become a very useful tool in organic synthesis. A comprehensive investigation into isolated organometallic intermediates and their reactivity within the catalytic cycle is lacking. We report here mechanistic studies of cobalt-catalyzed, aminoquinoline-directed C(sp2)–H functionalization. number Co(III) have been structurally characterized, including, for first time aminoquinoline system, complexes arising from migratory insertion cobalt–carbon bonds. The stoichiometric reactions cobalt(III) aryls with alkenes, alkynes, carbon monoxide, cyclic secondary amines, benzamides explored. oxidation state cobalt product-forming step depends on nature coupling component. Specifically, annulation alkynes carbonylation CO likely proceed via Co(I)/Co(III) cycle. Carbon–hydrogen alkenes as well benzamide homocoupling, (formally) Co(IV) species involve oxidatively induced reductive elimination.

Язык: Английский

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Nickel-Catalyzed Linear-Selective C–H Alkylation of N-Heteroarenes with Unactivated α-Olefins

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

Опубликована: Фев. 17, 2025

We herein describe the nickel-catalyzed C2–H alkylation of benzothiazoles with unactivated α-olefins by using Ni(IPr*OMe)[P(OEt)3]Br2/Mg catalytic system in which a variety linear alkylated high regioselectivity were formed under mild reaction conditions. This transformation showed good compatibility to bearing various functional groups, such as esters, acetals, silyl ethers, amines, silanes, and boronate esters. Furthermore, this is also suitable other typical N-heteroarenes including thiazoles, benzimidazoles, quinazolones, uracils, pyridines, caffeines, indoles. Thus, work provides rapid access diverse step atom economy.

Язык: Английский

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Insights into the mechanism of 3d transition-metal-catalyzed directed C(sp³)–H bond functionalization reactions

Chemical Society Reviews, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

This review provides an overview of the research advaces in Ni-, Cu-, Fe- and Co-catalyzed directed C(sp 3 )–H bond functionalization reactions; including design principles, mechanistic discussions, along with potential applications limitations.

Язык: Английский

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A Million-fold Increase in C-H Bond Acidity Gives Palladium a Key Advantage in C(sp3)-H Activation Compared to Nickel

Опубликована: Апрель 23, 2025

Carbon-hydrogen bond activation is a pillar of synthetic chemistry. While it generally accepted that Pd more facile than Ni in C-H catalysis, there are no experimental platforms available to directly compare the magnitude weakening between and prior scission. This work presents first direct measurements C(sp³)-H acidity (pK_a) dissociation free energy (BDFE) for species containing ligated alkane-palladium interaction (R₂CH₂---Pd), also known as an agostic interaction. Through standard-state equilibrium advanced computational modeling, we show acidifies bonds million times (6 pK_a units), indicating acidification key factor making privileged metal functionalization reactions. More broadly, these valuable findings help unravel fundamental performance differences Earth-abundant precious metals, potentially guiding future ligand design efforts catalysis.

Язык: Английский

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Fundamental Principles in Catalysis from Mechanistic Studies of Oxidative Decarboxylative Coupling Reactions

Accounts of Chemical Research, Год журнала: 2025, Номер unknown

Опубликована: Май 7, 2025

ConspectusOxidative decarboxylative coupling (ODC) reactions have been recognized as powerful alternatives to traditional cross-coupling due the ability generate (hetero)biaryl structures from simple and readily available carboxylic acid precursors. These reactions, however, are underdeveloped requirement for ortho-nitrobenzoate partners silver salts oxidants. Our research program has focused on development of new catalytic ODC well mechanistic studies these uncover origin synthetic limitations. As framework studies, we explored two key developed in our group: (1) a Ni-catalyzed arylation reaction that relies oxidant (2) Cu-catalyzed thiolation capable operating under aerobic conditions. findings, disclosed this Account, uncovered importance ortho-substituent revealed Ag-based oxidants also responsible mediating decarboxylation transmetalation steps.Systematic exploration series well-defined Ag-benzoate complexes allowed us probe ortho-nitro group step. Kinetic measurements large differently substituted benzoates were found correlate with field effect (F) ortho-substituent, revealing feature be enhanced reactivity favored benzoates.Our an unexpected redox step system. Synthesis isolation proposed nickelacycle Ag-aryl intermediates enabled direct study fundamental steps. Catalytic stoichiometric complexes, paired DFT calculations, supported which intermediate transfers aryl ligand AgI NiII concomitant oxidation NiIII-bis(aryl) intermediate.Finally, detailed demonstrated how catalyst system is able use O2 terminal oxidant. synthesis copper CuI-benzoate resting state, despite oxidizing conditions could support higher state intermediates. We identified intermediacy diphenyl disulfide (PhSSPh) formed thiophenol (PhSH) partner The PhSSPh proceeds via oxidative transfer PhS fragment CuI analogous observed arylation.These combined suggest significant implications more broadly. For example, it appears important when unable (as case nickel) but not needed efficient mediator its own copper). Furthermore, plays additional role required itself (such PhSSPh). anticipate insights will facilitate operate milder broader substrate scopes.

Язык: Английский

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