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

Accounts of Chemical Research, Journal Year: 2021, Volume and Issue: 54(17), P. 3415 - 3437

Published: Aug. 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.

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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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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Nickel‐CatalyzedDicarbofunctionalization of Alkenes^†

Chinese Journal of Chemistry, Journal Year: 2020, Volume and Issue: 38(11), P. 1371 - 1394

Published: June 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.

Language: 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, Journal Year: 2020, Volume and Issue: 142(48), P. 20390 - 20399

Published: Nov. 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.

Language: Английский

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

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(6), P. 4162 - 4184

Published: Jan. 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.

Language: Английский

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Nickel and Palladium Catalysis: Stronger Demand than Ever

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(2), P. 1180 - 1200

Published: Jan. 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

Language: Английский

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Photochemical C–H Activation Enables Nickel-Catalyzed Olefin Dicarbofunctionalization

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(10), P. 3901 - 3910

Published: March 4, 2021

Alkenes, ethers, and alcohols account for a significant percentage of bulk reagents available to the chemistry community. The petrochemical, pharmaceutical, agrochemical industries each consume gigagrams these materials as fuels solvents year. However, utilization such building blocks construction complex small molecules is limited by necessity prefunctionalization achieve chemoselective reactivity. Herein, we report implementation efficient, sustainable, diaryl ketone hydrogen-atom transfer (HAT) catalysis activate native C–H bonds multicomponent dicarbofunctionalization alkenes. ability forge new carbon–carbon between typically viewed commodity provides new, more atom-economic outlook organic synthesis. Through detailed experimental computational investigation, critical effect hydrogen bonding on reactivity this transformation was uncovered.

Language: Английский

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