Nickel-Catalyzed Enantioselective Reductive Cross-Coupling Reactions

ACS Catalysis, Год журнала: 2020, Номер 10(15), С. 8237 - 8246

Опубликована: Июнь 24, 2020

Nickel-catalyzed reductive cross-coupling reactions have emerged as powerful methods to join two electrophiles. These proven particularly useful for the coupling of sec-alkyl electrophiles form stereogenic centers; however, development enantioselective variants remains challenging. In this Perspective, we summarize progress that has been made toward Ni-catalyzed reactions.

Язык: Английский

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Nickel-Catalyzed Dicarbofunctionalization of Alkenes

ACS Catalysis, Год журнала: 2020, Номер 10(15), С. 8542 - 8556

Опубликована: Июль 2, 2020

1,2-Dicarbofunctionalization of alkenes has emerged as an efficient synthetic strategy for preparing substituted molecules by coupling readily available with electrophiles and/or nucleophiles. Nickel complexes serve effective catalysts owing to their tendency undergo facile oxidative addition and slow β-hydride elimination, capability access both two-electron radical pathways. Two-component alkene functionalization reactions have achieved high chemo-, regio-, stereoselectivities tethering one the partners substrate. Three-component reactions, however, often incorporate directing groups control selectivity. Only a few examples directing-group-free difunctionalizations unactivated been reported. Therefore, great opportunities exist development three-component difunctionalization broad substrate scopes tunable stereoselectivities.

Язык: Английский

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Cross-Electrophile Couplings of Activated and Sterically Hindered Halides and Alcohol Derivatives

Accounts of Chemical Research, Год журнала: 2020, Номер 53(9), С. 1833 - 1845

Опубликована: Авг. 25, 2020

ConspectusTransition metal catalyzed cross-electrophile coupling of alkyl electrophiles has evolved into a privileged strategy that permits the facile construction valuable C(sp3)–C bonds. Numerous elegant Ni-catalyzed methods, for example, arylation, allylation, acylation, and vinylation primary secondary halides have been developed. This prior work provided important mechanistic insights selectivity reactivity partners, which are largely dictated by both catalysts reactants. In spite advances made to date, number challenging issues remain, including (1) achieving stereoselective syntheses C–C bonds rely primarily on functionalized or activated precursors, (2) diversifying electrophiles, (3) gaining underlying reaction mechanisms.In this Account, we summarize Ni- Fe-catalyzed reductive bond forming methods developed in our laboratory, allowed us couple activated, sterically hindered tertiary C(sp3)–O access methylated trifluoromethylated products, esters, C-glycosides, quaternary carbon centers. We will begin with brief discussion chemoselective unactivated alkyl–alkyl bonds, focus effects ligands reductants, along leaving group-directed reactivities halides, role they play promoting methyl, trifluoromethyl, glycosyl chloroformates. Matching these suitable partners is considered essential success; something can be tuned means appropriate Ni catalysts. Second, detail how tuning steric electronic nickel labile pyridine-type additives (primarily MgCl2) effective creation arylated all-carbon centers through aryl encumbered halides. contrast, use bulkier bipyridine terpyridine incorporation relative small-sized acyl allyl groups acylated allylated Finally, show knowledge gained halide enabled develop permit oxalates allyl, aryl, vinyl wherein Barton C–O radical fragmentation mediated Zn MgCl2 promoted The same protocol applicable arylation derived from α-hydroxyl carbonyl substrates, involves formation relatively stable α-carbonyl centered radicals. Thus, Account not only summarizes synthetic allow using but also provides insight relationship between structure substrates catalysts, as well additives.

Язык: Английский

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Enantioselective Radical Reactions Using Chiral Catalysts

Chemical Reviews, Год журнала: 2022, Номер 122(6), С. 5842 - 5976

Опубликована: Янв. 24, 2022

Benefiting from the impressive increase in fundamental knowledge, last 20 years have shown a continuous burst of new ideas and consequently plethora catalytic methods for enantioselective radical reactions. This review aims to provide complete survey progress achieved over this latter period. The first part focuses on use chiral organocatalysts, these include catalysts covalently linked substrate those that interact with by weaker interactions like hydrogen bonds. second is devoted transition-metal redox catalysis which organized according increasing atomic number first-row transition metals (Ti, Cr, Fe, Mn, Co, Ni, Cu). Bioinspired manganese- iron-mediated hydroxylations oxidations are also discussed. A specific section dedicated reactivity Ru, Rh, Ir complexes as Lewis acids special focus at metal. Absorption photons result different events such energy transfer, single-electron hydrogen-atom transfer facilitating formation radicals. Organocatalysis has been successfully combined photocatalysts, opened pathways enlarging precursors available. merger photocatalysis organo- or metalla-photocatalysis brought novelty allowed discovery large original transformations. enzyme-catalyzed reactions involving intermediates largely benefit visible-light irradiation included review. provides comprehensive inventory goal detailing reaction mechanisms involved transformations any nonspecialist could find their own creativity invent yet unknown applications.

Язык: Английский

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Catalytic three-component dicarbofunctionalization reactions involving radical capture by nickel

Chemical Society Reviews, Год журнала: 2021, Номер 50(19), С. 10836 - 10856

Опубликована: Янв. 1, 2021

The catalytic dicarbofunctionalization of unsaturated π bonds represents a powerful platform for the rapid construction complex motifs. Despite remarkable progress, novel and efficient methods achieving such transformations under milder conditions with chemo-, regio-, stereoselectivity still remain significant challenge; thus, their development is highly desirable. Recently, merging nickel catalysis radical chemistry offers new benign unprecedented reactivity selectivity. In this review, we summarize recent advances in area by underpinning domino involving capture to provide clear overview reaction designs mechanistic scenarios.

Язык: Английский

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Transition Metal (Ni, Cu, Pd)-Catalyzed Alkene Dicarbofunctionalization Reactions

Accounts of Chemical Research, Год журнала: 2021, Номер 54(17), С. 3415 - 3437

Опубликована: Авг. 12, 2021

ConspectusRecently, alkene dicarbofunctionalization, i.e., the powerful organic synthesis method of difunctionalization with two carbon sources, emerged as a formidable reaction immense promise to synthesize complex molecules expeditiously from simple chemicals. This is generally achieved transition metals (TMs) through interception by sources an alkylmetal [β-H–C(sp3)–[M]] species, key intermediate prone undergo rapid β-H elimination. Related prior reports, since Paolo Chiusoli and Catellani's work in 1982 [ Tetrahedron Lett. 1982, 23, 4517], have used bicyclic disubstituted terminal alkenes, wherein elimination avoided geometric restriction or complete lack β-H's. With reasoning that β-H–C(sp3)–[M] intermediates could be rendered amenable use first row late TMs formation coordination-assisted transient metallacycles, these strategies were implemented address problem dicarbofunctionalization reactions.Because catalyze C(sp3)–C(sp3) coupling, Cu Ni anticipated impart sufficient stability intermediates, generated catalytically upon carbometalation, for their subsequent electrophiles/nucleophiles three-component reactions. Additionally, such innate property enable coupling partners entropically driven cyclization/coupling The cyclometalation concept stabilize intractable was hypothesized when reactions performed. idea curtail founded Whitesides's J. Am. Chem. Soc. 1976, 98, 6521] observation metallacycles much slower than acyclic alkylmetals.In this Account, examples demonstrate catalysts alkenylzinc reagents, alkyl halides, aryl halides afford carbo- heterocycles. In addition, forming nickellacycles enabled regioselective performance various alkenyl compounds. situ [M]-H alkenes after induced unprecedented metallacycle contraction process, which six-membered metal-containing rings shrank five-membered cycles, allowing creation new carbon–carbon bonds at allylic (1,3) positions. Applications are discussed.

Язык: Английский

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Electroreductive Carbofunctionalization of Alkenes with Alkyl Bromides via a Radical-Polar Crossover Mechanism

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(49), С. 20661 - 20670

Опубликована: Ноя. 24, 2020

Electrochemistry grants direct access to reactive intermediates (radicals and ions) in a controlled fashion toward selective organic transformations. This feature has been demonstrated variety of alkene functionalization reactions, most which proceed via an anodic oxidation pathway. In this report, we further expand the scope electrochemistry reductive alkenes. particular, strategic choice reagents reaction conditions enabled radical-polar crossover pathway wherein two distinct electrophiles can be added across highly chemo- regioselective fashion. Specifically, used strategy intermolecular carboformylation, anti-Markovnikov hydroalkylation, carbocarboxylation alkenes—reactions with rare precedents literature—by means electroreductive generation alkyl radical carbanion intermediates. These reactions employ readily available starting materials (alkyl halides, alkenes, etc.) simple, transition-metal-free display broad substrate good tolerance functional groups. A uniform protocol achieve all three transformations by simply altering medium. development provides new avenue for constructing Csp3–Csp3 bonds.

Язык: Английский

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Nickel‐CatalyzedDicarbofunctionalization of Alkenes^†

Chinese Journal of Chemistry, Год журнала: 2020, Номер 38(11), С. 1371 - 1394

Опубликована: Июнь 16, 2020

As a straightforward strategy for rapidly increasing molecular complexity, dicarbofunctionalization of alkenes has attracted substantial interests organic synthesis, medicine chemistry, and materials science. Nickel‐catalyzed cascade dicarbofunctionalizations have been flourished in this area recently, nickel‐mediated radical pathways particularly offer new opportunities conjunctive cross‐couplings with alkyl coupling partners. Herein, we give comprehensive review nickel‐catalyzed through historical perspective, including intermolecular three‐component reactions intramolecular reactions. Among the discussed review, carbometallation/cross‐coupling process addition/cross‐coupling are two major alkenes. The oxidative cyclization 1,2‐metallate shift processes also selectively discussed. These methods overcome limitations associated using noble metals field, providing an efficient access to structurally diversified molecules.

Язык: Английский

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General Method for Enantioselective Three-Component Carboarylation of Alkenes Enabled by Visible-Light Dual Photoredox/Nickel Catalysis

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(48), С. 20390 - 20399

Опубликована: Ноя. 19, 2020

A visible-light-promoted photoredox/nickel protocol for the enantioselective three-component carboarylation of alkenes with tertiary and secondary alkyltrifluoroborates aryl bromides is described. This redox-neutral allows facile divergent access to a wide array enantioenriched β-alkyl-α-arylated carbonyls, phosphonates, sulfones in high yields excellent enantioselectivities from readily available starting materials. We also report modular synthesis flurbiprofen analogs piragliatin lead compound demonstrate synthetic utility. Experimental computational mechanistic studies were performed gain insights into mechanism origin chemo- enantioselectivity.

Язык: Английский

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Nickel-catalyzed formation of quaternary carbon centers using tertiary alkyl electrophiles

Chemical Society Reviews, Год журнала: 2021, Номер 50(6), С. 4162 - 4184

Опубликована: Янв. 1, 2021

This review provides a comprehensive summary of recent advances in nickel-catalyzed reactions employing tertiary alkyl electrophiles for the construction quaternary carbon centers.

Язык: Английский

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