C–heteroatom coupling with electron-rich aryls enabled by nickel catalysis and light

Nature Catalysis, Год журнала: 2024, Номер 7(6), С. 733 - 741

Опубликована: Май 7, 2024

Abstract Nickel photoredox catalysis has resulted in a rich development of transition-metal-catalysed transformations for carbon–heteroatom bond formation. By harnessing light energy, the transition metal can attain oxidation states that are difficult to achieve through thermal chemistry catalytic manifold. For example, nickel reactions have been reported both synthesis anilines and aryl ethers from aryl(pseudo)halides. However, oxidative addition simple systems is often sluggish absence special, electron-rich ligands, leading catalyst decomposition. Electron-rich electrophiles therefore currently fall outside scope many field. Here we provide conceptual solution this problem demonstrate nickel-catalysed C–heteroatom bond-forming arylthianthrenium salts, including amination, oxygenation, sulfuration halogenation. Because redox properties salts primarily dictated by thianthrenium, highly donors be unlocked using NiCl 2 under irradiation form desired C‒heteroatom bonds.

Язык: Английский

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ProPhos: A Ligand for Promoting Nickel-Catalyzed Suzuki-Miyaura Coupling Inspired by Mechanistic Insights into Transmetalation

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(9), С. 6360 - 6368

Опубликована: Фев. 23, 2024

Nickel-catalyzed Suzuki–Miyaura coupling (Ni-SMC) offers the potential to reduce cost of pharmaceutical process synthesis. However, its application has been restricted by challenges such as slow reaction rates, high catalyst loading, and a limited scope heterocycles. Despite recent investigations, mechanism transmetalation in Ni-SMC, often viewed turnover-limiting step, remains insufficiently understood. We elucidate "Ni-oxo" pathway, applying PPh2Me ligand, identify formation nickel-oxo intermediate step. Building on this insight, we develop scaffolding ProPhos, featuring pendant hydroxyl group connected phosphine via linker. The design preorganizes both nucleophile nickel catalyst, thereby facilitating transmetalation. This exhibits fast kinetics robust activity across wide range heteroarenes, with loading 0.5–3 mol %. For arene substrates, can be further reduced 0.1

Язык: Английский

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Ratcheting synthesis

Nature Reviews Chemistry, Год журнала: 2023, Номер 8(1), С. 8 - 29

Опубликована: Дек. 15, 2023

Язык: Английский

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Synthesis of Nickel(I)–Bromide Complexes via Oxidation and Ligand Displacement: Evaluation of Ligand Effects on Speciation and Reactivity

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(35), С. 19368 - 19377

Опубликована: Авг. 23, 2023

Nickel’s +1 oxidation state has received much interest due to its varied and often enigmatic behavior in increasingly popular catalytic methods. In part, the lack of understanding about NiI results from common synthetic strategies limiting breadth complexes that are accessible for mechanistic study catalyst design. We report an oxidative approach using tribromide salts allows generation a well-defined precursor, [NiI(COD)Br]2, as well several new complexes. Included among them bearing bulky monophosphines, which structure–speciation relationships established reactivity Suzuki–Miyaura coupling (SMC) is investigated. Notably, these routes also allow synthesis monomeric t-Bubpy-bound complexes, not previously been achieved. These react with aryl halides, can enable challenging investigations present opportunities catalysis synthesis.

Язык: Английский

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LASP to the Future of Atomic Simulation: Intelligence and Automation

Precision Chemistry, Год журнала: 2024, Номер 2(12), С. 612 - 627

Опубликована: Сен. 14, 2024

Atomic simulations aim to understand and predict complex physical phenomena, the success of which relies largely on accuracy potential energy surface description efficiency capture important rare events. LASP software (large-scale atomic simulation with a Neural Network Potential), released in 2018, incorporates key ingredients fulfill ultimate goal by combining advanced neural network potentials efficient global optimization methods. This review introduces recent development along two main streams, namely, higher intelligence more automation, solve material reaction problems. The latest version (LASP 3.7) features many-body function corrected (G-MBNN) improve PES low cost, achieves linear scaling for large-scale simulations. functionalities are updated incorporate (i) ASOP ML-interface methods finding interface structures under grand canonic conditions; (ii) ML-TS MMLPS identify lowest pathway. With these powerful functionalities, now serves as an intelligent data generator create computational databases end users. We exemplify database construction zeolite metal-ligand properties new catalyst design.

Язык: Английский

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Machine Learning-Guided Development of Trialkylphosphine Ni^(I) Dimers and Applications in Site-Selective Catalysis

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(28), С. 15414 - 15424

Опубликована: Июль 6, 2023

Owing to the unknown correlation of a metal’s ligand and its resulting preferred speciation in terms oxidation state, geometry, nuclearity, rational design multinuclear catalysts remains challenging. With goal accelerate identification suitable ligands that form trialkylphosphine-derived dihalogen-bridged Ni(I) dimers, we herein employed an assumption-based machine learning approach. The workflow offers guidance space for desired without (or only minimal) prior experimental data points. We experimentally verified predictions synthesized numerous novel dimers as well explored their potential catalysis. demonstrate C–I selective arylations polyhalogenated arenes bearing competing C–Br C–Cl sites under 5 min at room temperature using 0.2 mol % newly developed dimer, [Ni(I)(μ-Br)PAd2(n-Bu)]2, which is so far unmet with alternative dinuclear or mononuclear Ni Pd catalysts.

Язык: Английский

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Predictive catalysis: a valuable step towards machine learning

Trends in Chemistry, Год журнала: 2023, Номер 5(12), С. 935 - 946

Опубликована: Ноя. 18, 2023

Язык: Английский

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Comparison of Monophosphine and Bisphosphine Precatalysts for Ni-Catalyzed Suzuki–Miyaura Cross-Coupling: Understanding the Role of the Ligation State in Catalysis

ACS Catalysis, Год журнала: 2023, Номер 13(12), С. 7966 - 7977

Опубликована: Май 30, 2023

Practical advances in Ni-catalyzed Suzuki-Miyaura cross-coupling (SMC) have been limited by a lack of mechanistic understanding phosphine ligand effects. While bisphosphines are commonly used these methodologies, we observed instances where monophosphines can provide comparable or higher levels reactivity. Seeking to understand the role ligation state catalysis, performed head-to-head comparison study C(sp2)-C(sp2) Ni SMCs catalyzed mono and bisphosphine precatalysts using six distinct substrate pairings. Significant variation optimal precatalyst was observed, with monophosphine tending outperform electronically deactivated sterically hindered substrates. Mechanistic experiments revealed for monoligated (P1Ni) species accelerating fundamental organometallic steps catalytic cycle, while highlighting need bisligated (P2Ni) avoid off-cycle reactivity catalyst poisoning heterocyclic motifs. These findings guidelines selection against challenging substrates future design tailored demands SMCs.

Язык: Английский

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Benchtop Nickel Catalysis Invigorated by Electron-Deficient Diene Ligands

Accounts of Chemical Research, Год журнала: 2024, Номер 57(3), С. 312 - 326

Опубликована: Янв. 18, 2024

ConspectusDue to the rarity of precious metals like palladium, nickel catalysis is becoming an increasingly important player in organic synthesis, especially for formation bonds with sp3-hybridized carbon centers. Traditionally, catalytic processes involving active Ni(0) species have relied on Ni(COD)2 or situ reduction Ni(II) salts. However, air- and temperature-sensitive material that requires use inert-atmosphere glovebox, protocols salts using metallic organometallic reductants add additional complications reaction development.This Account chronicles development air-stable precursors as replacements reduction. Based Schrauzer's seminal discovery Ni(COD)(DQ) zerovalent organonickel complex, our research laboratories at Scripps Research Bristol Myers Squibb developed a class precatalysts based Ni(COD)(EDD) (EDD = electron-deficient diene) framework, relying steric electronic properties supporting diene render metal center stable air, moisture, even silica gel but reactive ligand substitution redox changes.The complexes can be accessed through exchange Ni(COD)2, Ni(acac)2 DIBAL-H, electrochemically via cathodic followed by addition EDD one pot. As toolkit, demonstrate reactivity equivalent enhanced compared catalyzing C–C C–N cross-couplings, Miyaura borylations, C–H activations, other transformations. Since initial report Ni(COD)(DQ), its C(sp2)–CN activation, metallophotoredox, electric field-induced cross-coupling also been demonstrated.By incorporating precatalyst toolkit into campaigns, able perform C(sp3)–S(alkyl) couplings metallonitrenoid carboamination, both which represent challenging transformations were inaccessible traditional phosphine, nitrogen, olefin ligands. Computational experimental studies how quinone ligands are hemilabile, adopting η1(O)-bound geometries relieve strain stabilize transition states intermediates; redox-active, transiently oxidize center; electron-withdrawing -donating, depending oxidation state coordination geometry. These show enable key steps beyond imparting air-stability.Since documenting activity many observed unique this precatalyst. was found offer superior cross coupling form N,N-diaryl sulfonamides preparation biaryls from aryl halides benzene Ni-mediated, base-assisted homolytic aromatic substitution.

Язык: Английский

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Ligand Substitution, Catalyst Activation, and Oxidative Addition Studies of a Stable Dialkyl Palladium Precatalyst

Organometallics, Год журнала: 2025, Номер unknown

Опубликована: Янв. 6, 2025

Palladium-catalyzed cross-coupling reactions are indispensable in chemical synthesis, but efficient situ catalyst activation remains a persistent challenge. Current Pd(II) precatalysts often lead to inefficient activation, necessitating higher loadings and limiting selectivity. We investigated the ligand substitution mechanism of stable dialkyl complex (DMPDAB)Pd(CH2SiMe3)2 real-time using mass spectrometric monitoring. The introduction charge-tagged phosphine ligands enabled detection key catalytic intermediates identification off-cycle species. Our findings demonstrate low energy for dissociation DMPDAB reductive elimination (Me3SiCH2)2 resulting rapid formation monoligated LPd(0) species, active species oxidative addition. These mechanistic insights offer path toward developing more selective Pd-catalyzed processes, offering valuable guidance future design with improved performance.

Язык: Английский

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