Nickel-Catalyzed Enantioselective Reductive Cross-Coupling Reactions

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(15), P. 8237 - 8246

Published: June 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.

Language: Английский

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Recent developments in nickel-catalyzed intermolecular dicarbofunctionalization of alkenes

Chemical Science, Journal Year: 2020, Volume and Issue: 11(17), P. 4287 - 4296

Published: Jan. 1, 2020

Nickel-catalyzed three-component alkene difunctionalization has rapidly emerged as a powerful tool for forging two C-C bonds in single reaction. Building upon the modes of bond construction traditional two-component cross-coupling, various research groups have demonstrated versatility nickel enabling catalytic 1,2-dicarbofunctionalization using wide range carbon-based electrophiles and nucleophiles fully intermolecular fashion. Though this area only recently, last few years witnessed proliferation publications on topic, underscoring potential strategy to develop into general platform that offers high regio- stereoselectivity. This minireview highlights recent progress alkenes via catalysis discusses lingering challenges within reactivity paradigm.

Language: Английский

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Nickel-Catalyzed Dicarbofunctionalization of Alkenes

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(15), P. 8542 - 8556

Published: July 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.

Language: Английский

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Enantioselective Three-Component Fluoroalkylarylation of Unactivated Olefins through Nickel-Catalyzed Cross-Electrophile Coupling

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(21), P. 9604 - 9611

Published: May 11, 2020

A nickel-catalyzed, enantioselective, three-component fluoroalkylarylation of unactivated alkenes with aryl halides and perfluoroalkyl iodides has been described. This cross-electrophile coupling protocol utilizes a chiral nickel/BiOx system as well pendant chelating group to facilitate the challenging three-component, asymmetric difunctionalization alkenes, providing direct access valuable β-fluoroalkyl arylalkanes high efficiency excellent enantioselectivity. The mild conditions allow for broad substrate scope good functional toleration.

Language: Английский

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Catalytic three-component dicarbofunctionalization reactions involving radical capture by nickel

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(19), P. 10836 - 10856

Published: Jan. 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.

Language: Английский

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Asymmetric Ni-Catalyzed Radical Relayed Reductive Coupling

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(31), P. 13515 - 13522

Published: June 29, 2020

Alkene dicarbofunctionalizations enable the streamlined construction of aliphatic structures and have thus been subject intense research efforts. Despite significant progress, catalytic asymmetric variants remain scarce. Inspired by advantages reductive cross-coupling approaches, we present here a highly efficient intermolecular Ni-catalyzed dicarbofunctionalization alkenes. Two distinct readily available electrophiles, namely, Csp2- Csp3-halides, are added simultaneously across variety olefins (vinyl amides, vinyl boranes, phosphonates) at room temperature in regio- enantioselective manner. The reaction, devoid sensitive organometallic reagents, takes advantage an situ generated chiral alkyl Ni(III)-intermediate to ensure stereodefined outcome Csp3–Csp2 bond-forming reaction. An (l)-(+)-isoleucine bisoxazoline ligand presence coordinating sites on alkene key for successful these "asymmetric radical relayed couplings" (ARRRCs). Further, multiple transformations amides obtained this process showcase potential new methodology straightforward assembly building blocks such as primary secondary amines oxazolines, highlighting its synthetic utility.

Language: Английский

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Developments in Photoredox/Nickel Dual-Catalyzed 1,2-Difunctionalizations

Chem, Journal Year: 2020, Volume and Issue: 6(6), P. 1327 - 1339

Published: June 1, 2020

Language: Английский

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Mechanism of Ni-Catalyzed Reductive 1,2-Dicarbofunctionalization of Alkenes

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(44), P. 17937 - 17948

Published: Oct. 7, 2019

Ni-catalyzed cross-electrophile coupling reactions have emerged as appealing methods to construct organic molecules without the use of stoichiometric organometallic reagents. The mechanisms are complex: plausible pathways, such "radical chain" and "sequential reduction" mechanisms, dependent on sequence activation electrophiles. A combination kinetic, spectroscopic, studies reveals that a Ni-catalyzed, reductive 1,2-dicarbofunctionalization alkenes proceeds through pathway. reduction Ni by Zn is turnover-limiting step, consistent with Ni(II) intermediates catalyst resting-state. only sufficient reduce (phen)Ni(II) Ni(I) species. As result, commonly proposed Ni(0) absent under these conditions. (Phen)Ni(I)–Br selectively activates aryl bromides via two-electron oxidation addition, whereas alkyl activated (phen)Ni(I)–Ar single-electron afford radicals. These findings could provide insight into achieving selectivity between different

Language: Английский

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

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(49), P. 20661 - 20670

Published: Nov. 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.

Language: Английский

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Three-Component Olefin Dicarbofunctionalization Enabled by Nickel/Photoredox Dual Catalysis

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(51), P. 20069 - 20078

Published: Dec. 13, 2019

An intermolecular, photocatalytic dicarbofunctionalization (DCF) of olefins enabled by the merger Giese-type addition with Ni/photoredox dual catalysis has been realized. Capitalizing on rapid 3° radicals to alkenes and their reluctance toward single electron metalation Ni complexes, regioselective alkylation arylation is possible. This catalytic method not only permits elaborate species be assembled from commodity materials, but also allows quaternary tertiary centers installed in a singular, chemoselective olefin difunctionalization. multicomponent process occurs under exceptionally mild conditions, compatible diverse range functional groups synthetic handles such as pinacolboronate esters. technology was directly applied synthesis an intermediate preclinical candidate (TK-666) its derivatives.

Language: Английский

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