The Buchwald–Hartwig Amination After 25 Years

Angewandte Chemie International Edition, Год журнала: 2019, Номер 58(48), С. 17118 - 17129

Опубликована: Июнь 5, 2019

Abstract The Pd‐catalyzed coupling of aryl (pseudo)halides and amines is one the most powerful approaches for formation C(sp 2 )−N bonds. pioneering reports from Migita subsequently Buchwald Hartwig on aminostannanes bromides rapidly evolved into general practical tin‐free protocols with broad substrate scope, which led to establishment what now known as Buchwald–Hartwig amination. This Minireview summarizes evolution this cross‐coupling reaction over course past 25 years illustrates some recent applications well‐established methodology.

Язык: Английский

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Trends in the Usage of Bidentate Phosphines as Ligands in Nickel Catalysis

Chemical Reviews, Год журнала: 2020, Номер 120(13), С. 6124 - 6196

Опубликована: Июнь 3, 2020

A critically important process in catalysis is the formation of an active catalyst from combination a metal precursor and ligand, as efficacy this reaction governs amount catalyst. This Review comprehensive overview reactions catalyzed by nickel added bidentate phosphine, focusing on steps transforming precatalyst ligand into potential effects transformation catalysis. Reactions covered include common cross-coupling reactions, such Suzuki, Heck, Kumada, Negishi couplings, addition cycloadditions, C–H functionalizations, polymerizations, hydrogenations, reductive among others. Overall, most widely used with free phosphines Ni(cod)2, which accounts for ∼50% reports surveyed, distantly followed Ni(acac)2 Ni(OAc)2, account ∼10% each. By compiling these we have calculated statistics usage each Ni(cod)2 other sources. The are simple, relatively inexpensive ligands, DPPE, DCPE, DPPP, DPPB, along others more complex backbones, DPPF Xantphos. use expensive chiral scattered, but ligands BINAP, Me-Duphos, Josiphos, related analogs.

Язык: Английский

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Nickel and Palladium Catalysis: Stronger Demand than Ever

ACS Catalysis, Год журнала: 2022, Номер 12(2), С. 1180 - 1200

Опубликована: Янв. 5, 2022

Key similarities and differences of Pd Ni in catalytic systems are discussed. Overall, catalyze a vast number similar C–C C–heteroatom bond-forming reactions. However, the smaller atomic radius lower electronegativity Ni, as well more negative redox potentials low-valent species, often provide higher reactivity oxidative addition or insertion reactions persistence alkyl-Ni intermediates against β-hydrogen elimination, thus enabling activation reluctant electrophiles, including alkyl electrophiles. Another key point relates to stability open-shell electronic configurations Ni(I) Ni(III) compared with Pd(I) Pd(III). Nickel very involve interconvertible Ni(n+) active species variable oxidation states (Ni(0), Ni(I), Ni(II), Ni(III)). In contrast, involving Pd(III) still relatively less developed may require facilitation by special ligands merging photo- electrocatalysis. high Pd(n+) ensure their facile reduction Pd(0) under assistance numerous reagents solvents, providing concentrations molecular Pd1(0) complexes that can reversibly aggregate into Pdn clusters nanoparticles form cocktail Pdn(0) various nuclearities (i.e., values "n"). Ni(0) strong reductants; they sensitive deactivation air other oxidizers and, consequence, operate at catalyst loadings than palladium same The ease robustness versatility for catalysis, whereas variety enables diverse uncommon reactivity, albeit requiring efforts stabilization nickel systems. As discussion, we note easily "cocktail particles" different but (Pd1, Pdn, NPs), behave species" is stable nuclearities. Undoubtedly, there stronger demand ever not only develop improved efficient catalysts also understand mechanisms

Язык: Английский

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Palladium catalyzed C–C and C–N bond forming reactions: an update on the synthesis of pharmaceuticals from 2015–2020

Organic Chemistry Frontiers, Год журнала: 2020, Номер 8(2), С. 384 - 414

Опубликована: Ноя. 11, 2020

Some of the most prominent and promising catalysts in organic synthesis for requisite construction C–C C–N bonds are palladium (Pd) catalysts, which play a pivotal role pharmaceutical medicinal chemistry.

Язык: Английский

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Room-Temperature Cu-Catalyzed Amination of Aryl Bromides Enabled by DFT-Guided Ligand Design

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(12), С. 6966 - 6975

Опубликована: Март 16, 2023

Ullmann-type C-N coupling reactions represent an important alternative to well-established Pd-catalyzed approaches due the differing reactivity and lower cost of Cu. While design anionic Cu ligands, particularly those by Ma, has enabled various classes aryl halides alkyl amines, most methods require conditions that can limit their utility on complex substrates. Herein, we disclose development N1,N2-diarylbenzene-1,2-diamine ligands promote Cu-catalyzed amination bromides under mild conditions. Guided DFT calculations, these were designed (1) increase electron density Cu, thereby increasing rate oxidative addition bromides, (2) stabilize active CuI via a π-interaction. Under optimized conditions, structurally diverse heteroaryl broad range amine nucleophiles, including pharmaceuticals bearing multiple functional groups, efficiently coupled at room temperature. Combined computational experimental studies support mechanism bond formation follows catalytic cycle akin well-explored variants. Modification ligand structure include naphthyl residue resulted in energy barrier addition, providing 30-fold relative what is seen with other ligands. Collectively, results establish new class for couplings, which anticipate may be extended C-heteroatom C-C bond-forming reactions.

Язык: Английский

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Organic Solvent Nanofiltration in Pharmaceutical Applications

Organic Process Research & Development, Год журнала: 2024, Номер 28(4), С. 891 - 923

Опубликована: Март 22, 2024

Separation and purification in organic solvents are indispensable procedures pharmaceutical manufacturing. However, they still heavily rely on the conventional separation technologies of distillation chromatography, resulting high energy massive solvent consumption. As an alternative, nanofiltration (OSN) offers benefits low consumption, solid waste generation, easy scale-up incorporation into continuous processes. Thus, there is a growing interest employing membrane technology area to improve process sustainability efficiency. This Review comprehensively summarizes recent progress (especially last 10 years) its applications industry, including concentration active ingredients, homogeneous catalyst recovery, exchange OSN-assisted peptide/oligonucleotide synthesis. Furthermore, challenges future perspectives discussed detail.

Язык: Английский

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Aminative Suzuki–Miyaura coupling

Science, Год журнала: 2024, Номер 383(6686), С. 1019 - 1024

Опубликована: Фев. 29, 2024

The Suzuki-Miyaura and Buchwald-Hartwig coupling reactions are widely used to form carbon-carbon (C-C) carbon-nitrogen (C-N) bonds, respectively. We report the incorporation of a formal nitrene insertion process into reaction, altering products from C-C-linked biaryls C-N-C-linked diaryl amines thereby joining pathways same starting-material classes. A combination bulky ancillary phosphine ligand on palladium commercially available amination reagent enables efficient reactivity across aryl halides pseudohalides, boronic acids esters, many functional groups heterocycles. Mechanistic insights reveal flexibility order bond-forming events, suggesting potential for expansion aminative cross-coupling concept encompass diverse nucleophiles electrophiles as well four-component variants.

Язык: Английский

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Hydroarylation of Arenes via Reductive Radical-Polar Crossover

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(20), С. 9163 - 9168

Опубликована: Май 7, 2020

A photocatalytic system for the dearomative hydroarylation of benzene derivatives has been developed. Using a combination an organic photoredox catalyst and amine reductant, this process operates through reductive radical-polar crossover mechanism where aryl halide reduction triggers regioselective radical cyclization event, followed by anion formation quenching to produce range complex spirocyclic cyclohexadienes. This light-driven protocol functions at room temperature in green solvent (aq. MeCN) without need precious metal-based catalysts or reagents generation stoichiometric metal byproducts.

Язык: Английский

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Heterogeneous Catalysis for Cross-Coupling Reactions: An Underutilized Powerful and Sustainable Tool in the Fine Chemical Industry?

Organic Process Research & Development, Год журнала: 2021, Номер 25(4), С. 740 - 753

Опубликована: Март 30, 2021

Transition-metal-catalyzed cross-coupling reactions are among the most important processes in organic chemistry. For years, fine chemical industry has looked for a variety of ways to reduce amounts transition metals employed their transformations, particularly reactions. One interesting alternative consider is use heterogeneous catalysis because its potential benefits low metal levels postreaction and reusability. Numerous examples will be described this review that highlight advantages over more commonly homogeneous catalysts. Despite great potential, past decade seen decrease catalysts industry, fueled by perception difficult reaction understanding reproducibility. With emergence new generation supported catalysts, first-row catalysis, continuous flow technology, tools have been developed change reluctance toward industry. We hope captures attention participants field implement

Язык: Английский

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Strategies for sustainable palladium catalysis

Coordination Chemistry Reviews, Год журнала: 2021, Номер 442, С. 213925 - 213925

Опубликована: Май 14, 2021

Язык: Английский

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