The merger of transition metal and photocatalysis

Nature Reviews Chemistry, Год журнала: 2017, Номер 1(7)

Опубликована: Июль 5, 2017

Язык: Английский

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Visible‐Light Photocatalysis: Does It Make a Difference in Organic Synthesis?

Angewandte Chemie International Edition, Год журнала: 2018, Номер 57(32), С. 10034 - 10072

Опубликована: Фев. 21, 2018

Visible-light photocatalysis has evolved over the last decade into a widely used method in organic synthesis. Photocatalytic variants have been reported for many important transformations, such as cross-coupling reactions, α-amino functionalizations, cycloadditions, ATRA or fluorinations. To help chemists select photocatalytic methods their synthesis, we compare this Review classical and procedures selected classes of reactions highlight advantages limitations. In cases, proceed under milder reaction conditions, typically at room temperature, stoichiometric reagents are replaced by simple oxidants reductants, air, oxygen, amines. Does visible-light make difference synthesis? The prospect shuttling electrons back forth to substrates intermediates selectively transfer energy through visible-light-absorbing photocatalyst holds promise improve current radical chemistry open up new avenues accessing reactive species hitherto unknown, especially merging with organo- metal catalysis.

Язык: Английский

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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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Benzoxazole-Linked Ultrastable Covalent Organic Frameworks for Photocatalysis

Journal of the American Chemical Society, Год журнала: 2018, Номер 140(13), С. 4623 - 4631

Опубликована: Март 27, 2018

The structural uniqueness of covalent organic frameworks (COFs) has brought these new materials great potential for advanced applications. One the key aspects yet to be developed is how improve robustness covalently linked reticular frameworks. In order make best use π-conjugated structures, we develop herein a "killing two birds with one stone" strategy and construct series ultrastable benzoxazole-based COFs (denoted as LZU-190, LZU-191, LZU-192) metal-free photocatalysts. Benefiting from formation benzoxazole rings through reversible/irreversible cascade reactions, synthesized exhibit permanent stability in presence strong acid (9 M HCl), base NaOH), sunlight. Meanwhile, reticulation moiety into COF decreases optical band gap therefore increases capability visible-light absorption. As result, excellent photoactivity unprecedented recyclability LZU-190 (for at least 20 catalytic runs, each product yield 99%) have been illustrated visible-light-driven oxidative hydroxylation arylboronic acids phenols. This contribution represents first report on photocatalytic application which not only sheds light exploration robust organophotocatalysts small molecules extended but also offers in-depth understanding structure-activity relationship toward practical applications materials.

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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Photoredox-Mediated Routes to Radicals: The Value of Catalytic Radical Generation in Synthetic Methods Development

ACS Catalysis, Год журнала: 2017, Номер 7(4), С. 2563 - 2575

Опубликована: Март 14, 2017

Photoredox catalysis has experienced a revitalized interest from the synthesis community during past decade. For example, photoredox/Ni dual protocols have been developed to overcome several inherent limitations of palladium-catalyzed cross-couplings by invoking single-electron transmetalation pathway. This Perspective highlights advances made our laboratory since inception cross-coupling benzyltrifluoroborates with aryl bromides. In addition broadening scope trifluoroborate coupling partners, research using readily oxidized hypervalent silicates as radical precursors that demonstrate functional group compatibility is highlighted. The pursuit electrophilic partners beyond (hetero)aryl bromides also led incorporation new classes C(sp2)-hybridized substrates into light-mediated cross-coupling. Advances expand toolbox utilizing feedstock chemicals (e.g., aldehydes) access radicals were previously inaccessible trifluoroborates and are emphasized. Additionally, organic photocatalysts investigated replacements for their expensive iridium- ruthenium-based counterparts. Lastly, net C–H functionalization partner in an effort improve atom economy presented. An underlying theme all these studies value generating catalytic manner, rather than stoichiometrically.

Язык: Английский

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Technological Innovations in Photochemistry for Organic Synthesis: Flow Chemistry, High-Throughput Experimentation, Scale-up, and Photoelectrochemistry

Chemical Reviews, Год журнала: 2021, Номер 122(2), С. 2752 - 2906

Опубликована: Авг. 10, 2021

Photoinduced chemical transformations have received in recent years a tremendous amount of attention, providing plethora opportunities to synthetic organic chemists. However, performing photochemical transformation can be quite challenge because various issues related the delivery photons. These challenges barred widespread adoption steps industry. past decade, several technological innovations led more reproducible, selective, and scalable photoinduced reactions. Herein, we provide comprehensive overview these exciting advances, including flow chemistry, high-throughput experimentation, reactor design scale-up, combination photo- electro-chemistry.

Язык: Английский

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Cross-Coupling and Related Reactions: Connecting Past Success to the Development of New Reactions for the Future

Organometallics, Год журнала: 2018, Номер 38(1), С. 3 - 35

Опубликована: Ноя. 27, 2018

Cross-coupling reactions, which were discovered almost 50 years ago, are widely used in both industry and academia. Even though cross-coupling reactions now represent mature technology, there is still a significant amount of research this area that aims to improve the scope these develop more efficient catalysts, make practical. In tutorial, brief background provided, then major advances over last 20 described. These include development improved ligands precatalysts for extension much wider range electrophiles. For example, common with sp3-hybridized electrophiles as well ester, amide, ether, aziridine substrates. many modern substrates, traditional palladium-based catalysts less than systems based on first-row transition metals such nickel. Conventional have also inspired related cross-electrophile decarboxylative couplings metallaphotoredox chemistry. The new probably at same stage 30 tutorial highlights how strategies may be applicable making

Язык: Английский

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Photokatalyse mit sichtbarem Licht: Welche Bedeutung hat sie für die organische Synthese?

Angewandte Chemie, Год журнала: 2018, Номер 130(32), С. 10188 - 10228

Опубликована: Фев. 21, 2018

Abstract Die Photokatalyse mit sichtbarem Licht hat sich im letzten Jahrzehnt zu einer breit angewandten Methode in der organischen Synthese entwickelt. Für viele wichtige Reaktionen, wie Kreuzkupplungen, α‐Amino‐Funktionalisierungen, Cycloadditionen, ATRA‐Reaktionen oder Fluorierungen, wurden photokatalytische Varianten berichtet. Um Chemiker bei Auswahl photokatalytischer Methoden für ihre Synthesen unterstützen, vergleichen wir diesem Aufsatz klassische und Verfahren ausgewählte Reaktionsklassen zeigen deren Vorteile Grenzen auf. In vielen Fällen verlaufen die photokatalytischen Reaktionen unter milderen Reaktionsbedingungen, typischerweise Raumtemperatur, stöchiometrische Reagenzien werden durch einfache Oxidanzien Reduktionsmittel Luft, Sauerstoff Amine ersetzt. Beeinflusst organische Synthese? Aussicht, Elektronen Substraten Zwischenprodukten hin‐ herzuschieben Energie selektiv einen sichtbares absorbierenden Photokatalysatoren übertragen, verspricht aktuellen Radikalchemie verbessern neue Wege den Zugang reaktiven, bisher unbekannten Spezies erschließen, insbesondere das Zusammenspiel von Organo‐ Metallkatalyse.

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Photocatalytic Late-Stage C–H Functionalization

Chemical Reviews, Год журнала: 2023, Номер 123(8), С. 4237 - 4352

Опубликована: Янв. 24, 2023

The emergence of modern photocatalysis, characterized by mildness and selectivity, has significantly spurred innovative late-stage C–H functionalization approaches that make use low energy photons as a controllable source. Compared to traditional strategies, photocatalysis paves the way toward complementary and/or previously unattainable regio- chemoselectivities. Merging compelling benefits with workflow offers potentially unmatched arsenal tackle drug development campaigns beyond. This Review highlights photocatalytic strategies small-molecule drugs, agrochemicals, natural products, classified according targeted bond newly formed one. Emphasis is devoted identifying, describing, comparing main mechanistic scenarios. draws critical comparison between established ionic chemistry photocatalyzed radical-based manifolds. aims establish current state-of-the-art illustrate key unsolved challenges be addressed in future. authors aim introduce general readership functionalization, specialist practitioners evaluation methodologies, potential for improvement, future uncharted directions.

Язык: Английский

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