Metallaphotoredox: The Merger of Photoredox and Transition Metal Catalysis

Chemical Reviews, Год журнала: 2021, Номер 122(2), С. 1485 - 1542

Опубликована: Ноя. 18, 2021

The merger of photoredox catalysis with transition metal catalysis, termed metallaphotoredox has become a mainstay in synthetic methodology over the past decade. Metallaphotoredox combined unparalleled capacity for bond formation broad utility photoinduced electron- and energy-transfer processes. Photocatalytic substrate activation allowed engagement simple starting materials metal-mediated bond-forming Moreover, electron or energy transfer directly key organometallic intermediates provided novel modes entirely complementary to traditional catalytic platforms. This Review details contextualizes advancements molecule construction brought forth by metallaphotocatalysis.

Язык: Английский

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The Persistent Radical Effect in Organic Synthesis

Angewandte Chemie International Edition, Год журнала: 2019, Номер 59(1), С. 74 - 108

Опубликована: Май 22, 2019

Abstract Radical–radical couplings are mostly nearly diffusion‐controlled processes. Therefore, the selective cross‐coupling of two different radicals is challenging and not a synthetically valuable transformation. However, if have lifetimes they generated at equal rates, will become dominant process. This high cross‐selectivity based on kinetic phenomenon called persistent radical effect (PRE). In this Review, an explanation PRE supported by simulations simple model systems provided. Radical stabilities discussed within context their lifetimes, various examples PRE‐mediated radical–radical in synthesis summarized. It shown that restricted to coupling with transient radical. If one partner longer‐lived than other radical, operates achieved. important point expands scope chemistry. The Review divided into parts, namely 1) or organic 2) “radical–metal crossover reactions”; here, metal‐centered species more generally transition‐metal complexes able react discussed—a field has flourished recently.

Язык: Английский

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Alkyl Carbon–Carbon Bond Formation by Nickel/Photoredox Cross‐Coupling

Angewandte Chemie International Edition, Год журнала: 2018, Номер 58(19), С. 6152 - 6163

Опубликована: Окт. 6, 2018

The union of photoredox and nickel catalysis has resulted in a renaissance radical chemistry as well the use nickel-catalyzed transformations, specifically for carbon-carbon bond formation. Collectively, these advances address longstanding challenge late-stage cross-coupling functionalized alkyl fragments. Empowered by notion that photocatalytically generated radicals readily undergo capture Ni complexes, wholly new feedstocks have been realized. Herein, we highlight recent developments several types cross-couplings are accessible exclusively through this approach.

Язык: Английский

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Applications of Halogen-Atom Transfer (XAT) for the Generation of Carbon Radicals in Synthetic Photochemistry and Photocatalysis

Chemical Reviews, Год журнала: 2021, Номер 122(2), С. 2292 - 2352

Опубликована: Дек. 9, 2021

The halogen-atom transfer (XAT) is one of the most important and applied processes for generation carbon radicals in synthetic chemistry. In this review, we summarize highlight aspects associated with XAT impact it has had on photochemistry photocatalysis. organization material starts analysis mechanistic then follows a subdivision based nature reagents used halogen abstraction. This review aims to provide general overview fundamental concepts main agents involved objective offering tool understand facilitate development new radical strategies.

Язык: Английский

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Photons or Electrons? A Critical Comparison of Electrochemistry and Photoredox Catalysis for Organic Synthesis

Chemical Reviews, Год журнала: 2021, Номер 122(2), С. 2487 - 2649

Опубликована: Ноя. 9, 2021

Redox processes are at the heart of synthetic methods that rely on either electrochemistry or photoredox catalysis, but how do and catalysis compare? Both approaches provide access to high energy intermediates (e.g., radicals) enable bond formations not constrained by rules ionic 2 electron (e) mechanisms. Instead, they 1e mechanisms capable bypassing electronic steric limitations protecting group requirements, thus enabling chemists disconnect molecules in new different ways. However, while providing similar intermediates, differ several physical chemistry principles. Understanding those differences can be key designing transformations forging disconnections. This review aims highlight these similarities between comparing their underlying principles describing impact electrochemical photochemical methods.

Язык: Английский

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1,4-Dihydropyridines as Alkyl Radical Precursors: Introducing the Aldehyde Feedstock to Nickel/Photoredox Dual Catalysis

ACS Catalysis, Год журнала: 2016, Номер 6(12), С. 8004 - 8008

Опубликована: Окт. 27, 2016

A Ni/photoredox dual catalytic cross-coupling is disclosed in which a diverse range of (hetero)aryl bromides are used as electrophiles, with 1,4-dihydropyridines serving precursors to Csp3-centered alkyl radical coupling partners. The reported method characterized by its extremely mild reaction conditions, enabling access underexplored cores.

Язык: Английский

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Enantioselective Electroreductive Coupling of Alkenyl and Benzyl Halides via Nickel Catalysis

ACS Catalysis, Год журнала: 2019, Номер 9(8), С. 6751 - 6754

Опубликована: Июнь 25, 2019

An electrochemically-driven enantioselective nickel-catalyzed reductive cross-coupling of alkenyl bromides and benzyl chlorides is reported. The reaction forms products bearing allylic stereogenic centers with good enantioselectivity under mild conditions in an undivided cell. Electrochemical activation turnover the catalyst mitigate issues posed by metal powder reductants. This report demonstrates that Ni-catalyzed cross-electrophile couplings can be driven electrochemically.

Язык: Английский

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Nickel-Catalyzed Defluorinative Reductive Cross-Coupling of gem-Difluoroalkenes with Unactivated Secondary and Tertiary Alkyl Halides

Journal of the American Chemical Society, Год журнала: 2017, Номер 139(36), С. 12632 - 12637

Опубликована: Авг. 29, 2017

Herein, we described a nickel-catalyzed monofluoroalkenylation through defluorinative reductive cross-coupling of gem-difluoroalkenes with alkyl halides. Key to the success this strategy is combination C–F cleavage halides activation. This reaction enables convenient synthesis large variety functionalized monofluoroalkenes under mild conditions broad functional group compatibility and excellent Z-selectivity. The Ni catalysis (Bpin)2/K3PO4 as terminal reductant promoted efficient C(sp2)–C(sp3) formation especially generation all-carbon quaternary centers high chemoselectivity.

Язык: Английский

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Remote Migratory Cross-Electrophile Coupling and Olefin Hydroarylation Reactions Enabled by in Situ Generation of NiH

Journal of the American Chemical Society, Год журнала: 2017, Номер 139(39), С. 13929 - 13935

Опубликована: Сен. 7, 2017

A highly efficient strategy for remote reductive cross-electrophile coupling has been developed through the ligand-controlled nickel migration/arylation. This general protocol allows use of abundant and bench-stable alkyl bromides aryl synthesis a wide range structurally diverse 1,1-diarylalkanes in excellent yields high regioselectivities under mild conditions. We also demonstrated that bromide could be replaced by proposed olefin intermediate while using n-propyl bromide/Mn0 as potential hydride source.

Язык: Английский

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

Chem, Год журнала: 2020, Номер 6(6), С. 1327 - 1339

Опубликована: Июнь 1, 2020

Язык: Английский

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