Synthetic Methods Driven by the Photoactivity of Electron Donor–Acceptor Complexes

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(12), С. 5461 - 5476

Опубликована: Март 5, 2020

The association of an electron-rich substrate with electron-accepting molecule can generate a new molecular aggregate in the ground state, called electron donor-acceptor (EDA) complex. Even when two precursors do not absorb visible light, resulting EDA complex often does. In 1952, Mulliken proposed quantum-mechanical theory to rationalize formation such colored complexes. However, and besides few pioneering studies 20th century, it is only past years that photochemistry has been recognized as powerful strategy for expanding potential visible-light-driven radical synthetic chemistry. Here, we explain why this photochemical approach was overlooked so long. We critically discuss historical context, scientific reasons, serendipitous observations, landmark discoveries were essential progress field. also outline future directions identify key advances are needed fully exploit photochemistry.

Язык: Английский

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4CzIPN-^tBu-Catalyzed Proton-Coupled Electron Transfer for Photosynthesis of Phosphorylated N-Heteroaromatics

Journal of the American Chemical Society, Год журнала: 2020, Номер 143(2), С. 964 - 972

Опубликована: Дек. 29, 2020

2,4,5,6-Tetrakis(3,6-di-tert-butyl-9H-carbazol-9-yl)isophthalonitrile (4CzIPN-tBu) was developed as a photocatalyst for the phosphorus-radical-initiated cascade cyclization reaction of isocyanides. By using 4CzIPN-tBu catalyst, we visible-light-induced proton-coupled electron transfer strategy generation phosphorus-centered radicals, via which wide range phosphorylated phenanthridines, quinolines, and benzothiazoles were successfully constructed.

Язык: Английский

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Synthetic reactions driven by electron-donor–acceptor (EDA) complexes

Beilstein Journal of Organic Chemistry, Год журнала: 2021, Номер 17, С. 771 - 799

Опубликована: Апрель 6, 2021

The reversible, weak ground-state aggregate formed by dipole–dipole interactions between an electron donor and acceptor is referred to as electron-donor–acceptor (EDA) complex. Generally, upon light irradiation, the EDA complex turns into excited state, causing transfer give radicals initiate subsequent reactions. Besides external energy source, reactions involving participation of complexes are mild, obviating transition metal catalysts or photosensitizers in majority cases line with theme green chemistry. This review discusses synthetic concerned well mechanisms that have been shown over past five years.

Язык: Английский

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Visible-light-initiated tandem synthesis of difluoromethylated oxindoles in 2-MeTHF under additive-, metal catalyst-, external photosensitizer-free and mild conditions

Chinese Chemical Letters, Год журнала: 2021, Номер 32(6), С. 1907 - 1910

Опубликована: Янв. 18, 2021

Язык: Английский

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Progress in Photoinduced Radical Reactions using Electron Donor‐Acceptor Complexes

Asian Journal of Organic Chemistry, Год журнала: 2021, Номер 10(4), С. 711 - 748

Опубликована: Фев. 11, 2021

Abstract Photocatalyzed organic synthesis transformation is a remarkable green synthetic strategy because of the advantages operational simplicity, high chemoselectivities, cheap, and environmental benignancy, along with extensive applications in fields organic, pharmaceutical functional material chemistry. Generally, photoredox catalysts or photosensitizers are necessary for generation their excited states to perform successive oxidative reductive reactions through single electron transfer (SET) energy (ET) process. Furthermore, exploration colored donor‐acceptor (EDA) complex charge (CT) between an electron‐rich electron‐poor substrate provides chance deliver intermediate under irradiation light, resulting formation radical activate species induce various reactions. These were performed without need any external photocatalysts mild reaction conditions. Herein, this review focuses on recent progress photoinduced addition reactions, borylations, radical‐radical cross‐coupling degradation cascade cyclization via EDA complexes. We highlight these novel methodologies applications, as well mechanisms. This will help provide references medicinal chemists who charmed by photochemical transformations based

Язык: Английский

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Shining light on halogen-bonding complexes: a catalyst-free activation mode of carbon–halogen bonds for the generation of carbon-centered radicals

Chemical Science, Год журнала: 2023, Номер 14(21), С. 5545 - 5568

Опубликована: Янв. 1, 2023

This review provides a comprehensive overview on examples of how photochemical excitation halogen-bonding complexes can be useful for the generation carbon-centered radicals and their participation in synthetic organic transformations.

Язык: Английский

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Transition-metal-free C–S bond cleavage and transformation of organosulfur compounds

Chemical Communications, Год журнала: 2023, Номер 59(36), С. 5343 - 5364

Опубликована: Янв. 1, 2023

The activation and transformation of organic chemical bonds is a fundamental scientific problem. In the past several decades, C-S bond cleavage for construction C-C C-heteroatom has received tremendous attention in chemistry. Although significant progress been made field transition metal strategies, variety novel transition-metal-free strategies have also developed using halogenated reagents, oxidants, acids, bases. Moreover, photochemical electrochemical methods to achieve organosulfur compounds. To date, however, no comprehensive review reported. Therefore, we herein provide major advances compounds, including thioethers, sulfoxides, sulfones, thioacetals, sulfonium salts, sulfur ylides.

Язык: Английский

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Visible-Light-Initiated Decarboxylative Alkylation of Quinoxalin-2(1H)-ones with Phenyliodine(III) Dicarboxylates in Recyclable Ruthenium(II) Catalytic System

ACS Sustainable Chemistry & Engineering, Год журнала: 2019, Номер 7(16), С. 14153 - 14160

Опубликована: Июль 15, 2019

A efficient and sustainable approach for the synthesis of 3-alkylquinoxalin-2(1H)-ones has been developed through visible-light-mediated decarboxylative alkylation quinoxalin-2(1H)-ones with phenyliodine(III) dicarboxylates. This photocatalytic reaction could be conducted at ambient temperature by employing eco-friendly PEG-200 as medium. Various were easily obtained present ruthenium(II) catalytic system, which successfully recycled five times without significant decrease its efficiency.

Язык: Английский

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The concept of dual roles design in clean organic preparation

Chinese Chemical Letters, Год журнала: 2019, Номер 30(12), С. 2132 - 2138

Опубликована: Сен. 19, 2019

Язык: Английский

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Visible-light-induced intramolecular charge transfer in the radical spirocyclisation of indole-tethered ynones

Chemical Science, Год журнала: 2019, Номер 11(5), С. 1353 - 1360

Опубликована: Дек. 13, 2019

Indole-tethered ynones form an intramolecular electron donor–acceptor complex that can undergo visible-light-induced charge transfer to promote thiyl radical generation from thiols. This initiates a novel chain sequence, based on dearomatising spirocyclisation with concomitant C–S bond formation. Sulfur-containing spirocycles are formed in high yields using this simple and mild synthetic protocol, which neither transition metal catalysts nor photocatalysts required. The proposed mechanism is supported by various mechanistic studies, the unusual initiation mode represents only second report of use synthesis.

Язык: Английский

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