Unveiling Extreme Photoreduction Potentials of Donor–Acceptor Cyanoarenes to Access Aryl Radicals from Aryl Chlorides

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(33), С. 13266 - 13273

Опубликована: Авг. 16, 2021

Since the seminal work of Zhang in 2016, donor–acceptor cyanoarene-based fluorophores, such as 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN), have been widely applied photoredox catalysis and used excellent metal-free alternatives to noble metal Ir- Ru-based photocatalysts. However, all reported reactions involving this chromophore family are based on harnessing energy from a single visible light photon, with limited range redox potentials −1.92 +1.79 V vs SCE. Here, we document unprecedented discovery that fluorophores can undergo consecutive photoinduced electron transfer (ConPET) achieve very high reduction potentials. One newly synthesized catalysts, 2,4,5-tri(9H-carbazol-9-yl)-6-(ethyl(phenyl)amino)isophthalonitrile (3CzEPAIPN), possesses long-lived (12.95 ns) excited radical anion form, 3CzEPAIPN•–*, which be activate reductively recalcitrant aryl chlorides (Ered ≈ −1.9 −2.9 SCE) under mild conditions. The resultant radicals engaged synthetically valuable aromatic C–B, C–P, C–C bond formation furnish arylboronates, arylphosphonium salts, arylphosphonates, spirocyclic cyclohexadienes.

Язык: Английский

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Electrophotocatalysis: Combining Light and Electricity to Catalyze Reactions

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(28), С. 12567 - 12583

Опубликована: Июль 11, 2022

Visible-light photocatalysis and electrocatalysis are two powerful strategies for the promotion of chemical reactions that have received tremendous attention in recent years. In contrast, processes combine these modalities, an area termed electrophotocatalysis, until recently remained quite rare. However, over past several years a number reports this shown potential combining power light electrical energy to realize new catalytic transformations. Electrophotocatalysis offers ability perform photoredox without need large quantities stoichiometric or superstoichiometric oxidants reductants by making use electrochemical as electron source sink. addition, electrophotocatalysis is readily amenable generation open-shell photocatalysts, which tend exceptionally strong redox potentials. way, potent yet selective been realized under relatively mild conditions. This Perspective highlights advances provides some possible avenues future work growing area.

Язык: Английский

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Atom Transfer Radical Polymerization: A Mechanistic Perspective

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(34), С. 15413 - 15430

Опубликована: Июль 26, 2022

Since its inception, atom transfer radical polymerization (ATRP) has seen continuous evolution in terms of the design catalyst and reaction conditions; today, it is one most useful techniques to prepare well-defined polymers as well notable examples catalysis polymer chemistry. This Perspective highlights fundamental advances ATRP reactions catalysts, focusing on crucial role that mechanistic studies play understanding, rationalizing, predicting outcomes. A critical summary traditional systems provided first; we then focus recent developments improve selectivity, control polymerizations via external stimuli, employ new photochemical or dual catalytic with an outlook future research directions open challenges.

Язык: Английский

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Synthetic Molecular Photoelectrochemistry: New Frontiers in Synthetic Applications, Mechanistic Insights and Scalability

Angewandte Chemie International Edition, Год журнала: 2021, Номер 61(12)

Опубликована: Сен. 3, 2021

Synthetic photoelectrochemistry (PEC) is receiving increasing attention as a new frontier for the generation and handling of reactive intermediates. PEC permits selective single-electron transfer (SET) reactions in much greener way broadens redox window possible transformations. Herein, most recent contributions are reviewed, demonstrating exciting opportunities, namely, combination with other reactivity paradigms (hydrogen-atom transfer, radical polar crossover, energy sensitization), scalability up to multigram scale, novel selectivities SET super-oxidations/reductions importance precomplexation temporally enable excited ion catalysis.

Язык: Английский

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Electro-/photocatalytic alkene-derived radical cation chemistry: recent advances in synthetic applications

Chemical Society Reviews, Год журнала: 2022, Номер 51(16), С. 7206 - 7237

Опубликована: Янв. 1, 2022

This review covers the recent progress in electro-/photo-catalytic alkene-derived radical cation chemistry for organic synthesis, including synthetic strategies, plausible mechanisms and further research outlook.

Язык: Английский

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C–H Amination via Electrophotocatalytic Ritter-type Reaction

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(23), С. 8597 - 8602

Опубликована: Июнь 2, 2021

A method for C–H bond amination via an electrophotocatalytic Ritter-type reaction is described. The catalyzed by a trisaminocyclopropenium (TAC) ion in electrochemical cell under irradiation. These conditions convert benzylic bonds to acetamides without the use of stoichiometric chemical oxidant. range functionality shown be compatible with this transformation, and several complex substrates are demonstrated.

Язык: Английский

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Recent progress in cathodic reduction-enabled organic electrosynthesis: Trends, challenges, and opportunities

eScience, Год журнала: 2022, Номер 2(3), С. 243 - 277

Опубликована: Апрель 23, 2022

Compared with general redox chemistry, electrochemistry using the electron as a potent, controllable, yet traceless alternative to chemical oxidants/reductants usually offers more sustainable options for achieving selective organic synthesis. With its environmentally benign features gradually being uncovered and studied, electrosynthesis is currently undergoing revival becoming rapidly growing area within synthetic community. Among electrochemical transformations, anodically enabled ones have been far extensively exploited than those driven by cathodic reduction, although both approaches are conceptually attractive. To stimulate development of cathodically reactions, this review summarizes recently developed reductive electrosynthetic protocols, discussing highlighting reaction features, substrate scopes, applications, plausible mechanisms reveal recent trends in area. Herein, reduction-enabled preparative transformations categorized into four types: reduction (1) unsaturated hydrocarbons, (2) heteroatom-containing carbon-based systems, (3) saturated C-hetero or C–C polar/strained bonds, (4) hetero-hetero linkages. Apart from net electroreductive few examples photo-electrosynthesis well paired electrolysis also introduced, which offer opportunities overcome certain limitations improve versatility. The electrochemically driven, transition metal-catalyzed cross-couplings that comprehensively discussed several other reviews not included here.

Язык: Английский

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Photo-/electrocatalytic functionalization of quinoxalin-2(1H)-ones

CHINESE JOURNAL OF CATALYSIS (CHINESE VERSION), Год журнала: 2021, Номер 42(11), С. 1921 - 1943

Опубликована: Авг. 30, 2021

Язык: Английский

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Carbon dioxide cycle via electrocatalysis: Electrochemical carboxylation of CO2 and decarboxylative functionalization of carboxylic acids

Green Synthesis and Catalysis, Год журнала: 2021, Номер 2(1), С. 19 - 26

Опубликована: Фев. 1, 2021

As one of the most important biogeochemical cycles, carbon dioxide (CO2) cycle between atmosphere and biosphere has a profound impact on life earth. Therefore, search for sustainable solutions to normalize currently unbalanced is central research topic many scientific disciplines. The green electrocatalysis offers very promising answer cycle. In this review, recent advances in enabled CO2 including electrochemical carboxylation decarboxylative functionalization carboxylic acids are highlighted.

Язык: Английский

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Oxidase reactions in photoredox catalysis

Chemical Society Reviews, Год журнала: 2021, Номер 50(5), С. 2954 - 2967

Опубликована: Янв. 1, 2021

The nature of the terminal oxidant in oxidation reactions is an important reaction variable that can profoundly impact mechanism, efficiency, and practicality a synthetic protocol. One might reasonably categorize catalytic into either "oxygenase" type reactions, which serves as atom- or group-transfer reagent, "oxidase" where involved catalyst turnover but does not become structurally incorporated product. As field photoredox catalysis has matured over past decade, many successful oxygenase-type photoreactions have been reported. development photocatalytic oxidase on other hand, somewhat slower. This tutorial review presents selected examples some key classes oxidants used design transformations, along with mechanistic features benefits each.

Язык: Английский

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