Solar Energy Catalysis

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(29)

Published: April 26, 2022

When it comes to using solar energy promote catalytic reactions, photocatalysis technology is the first choice. However, sunlight can not only be directly converted into chemical through a photocatalytic process, also different energy-transfer pathways. Using as source, reactions proceed independently, and coupled with other technologies enhance overall efficiency. Therefore, sunlight-driven are diverse, need given specific definition. We propose timely perspective for driven by give them definition, namely "solar catalysis". The concept of types catalysis, such photocatalysis, photothermal cell powered electrocatalysis, pyroelectric highlighted. Finally, their limitations future research directions discussed.

Language: Английский

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Formation and degradation of strongly reducing cyanoarene-based radical anions towards efficient radical anion-mediated photoredox catalysis

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Jan. 6, 2023

Cyanoarene-based photocatalysts (PCs) have attracted significant interest owing to their superior catalytic performance for radical anion mediated photoredox catalysis. However, the factors affecting formation and degradation of cyanoarene-based PC (PC•‒) are still insufficiently understood. Herein, we therefore investigate PC•‒ under widely-used photoredox-mediated reaction conditions. By screening various PCs, elucidate strategies efficiently generate with adequate excited-state reduction potentials (Ered*) via supra-efficient generation long-lived triplet excited states (T1). To thoroughly behavior in actual reactions, a reductive dehalogenation is carried out as model identified dominant photodegradation pathways PC•‒. Dehalogenation coexistent depending on rate electron transfer (ET) substrate strongly depends electronic steric properties PCs. Based understanding both PC•‒, demonstrate that efficient highly reducing allows catalyzed aryl/alkyl halides at loading low 0.001 mol% high oxygen tolerance. The present work provides new insights into reactions reactions.

Language: Английский

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Recent Advances in Electron Donor‐Acceptor (EDA)‐Complex Reactions involving Quaternary Pyridinium Derivatives

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(10), P. 1538 - 1564

Published: March 6, 2023

Abstract Quaternary pyridinium compounds are valuable intermediates in organic synthesis, which have gained immense popularity the synthetic community. The application of transition metal or photoredox catalysis transforming quaternary into various C−C and C−X bonds is well established. A majority these methods require high temperatures, expansive catalysts, delicate conditions for successful execution. On other hand, use metal‐free photocatalysis‐free strategies constructing using derivatives has been sought‐after. In this context, electron‐donor‐acceptor (EDA)‐complex reactions emerged as a state‐of‐the‐art methodology, do not any photocatalyst their EDA‐complex photochemistry takes advantage electron‐acceptor ability derivatives, can quickly generate radical precursor via deaminative process. These newly generated useful several transformations. We hereby, review, discuss an area major progress mediated involving with mechanism, substrate scope, limitations. magnified image

Language: Английский

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Organophotocatalytic Mechanisms: Simplicity or Naïvety? Diverting Reactive Pathways by Modifications of Catalyst Structure, Redox States and Substrate Preassemblies

ChemCatChem, Journal Year: 2023, Volume and Issue: 15(11)

Published: Feb. 21, 2023

Abstract Photocatalysis is a powerful tool to assemble diverse chemical scaffolds, yet bottleneck on its further development the understanding of multitude possible pathways when practitioners rely only oversimplified thermodynamic and optical factors. Recently, there growing number studies in field that exploit, inter alia , kinetic parameters organophotocatalysts are synthetically more programmable terms their redox states opportunities for aggregation with target substrate. Non‐covalent interactions play key role enables access new generation reactivities such as those open‐shell organophotocatalysts. In this review, we discuss how targeted structural modifications influence organophotocatalytic mechanisms together underlying principles. We also highlight benefits strategies preassembly static quenching overcome common reactivity issues (e. g., diffusion rate limits energetic limits).

Language: Английский

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Electron‐Poor Acridones and Acridiniums as Super Photooxidants in Molecular Photoelectrochemistry by Unusual Mechanisms

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(44)

Published: Aug. 16, 2023

Abstract Electron‐deficient acridones and in situ generated acridinium salts are reported as potent, closed‐shell photooxidants that undergo surprising mechanisms. When bridging acyclic triarylamine catalysts with a carbonyl group (acridones), this completely diverts their behavior away from open‐shell, radical cationic, ‘beyond diffusion’ photocatalysis to closed‐shell, neutral, diffusion‐controlled photocatalysis. Brønsted acid activation of dramatically increases excited state oxidation power (by +0.8 V). Upon reduction protonated acridones, they transform electron‐deficient even more potent (* E 1/2 =+2.56–3.05 V vs SCE). These oxidize arenes where conventional salt have thusfar been limited electron‐rich arenes. Surprisingly, upon photoexcitation these appear two electron reductive quenching form acridinide anions, spectroscopically‐detected forms. This new behaviour is partly enabled by catalyst preassembly the arene, contrasts SET salts. Critically, study illustrates how redox active chromophoric molecules initially considered photocatalysts can during reaction catalytically species different spectroscopic properties.

Language: Английский

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Photocatalytic C−F Bond Activation of Fluoroarenes, gem‐Difluoroalkenes and Trifluoromethylarenes

Asian Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 10(10), P. 2454 - 2472

Published: Aug. 18, 2021

Abstract Fluorine‐containing compounds have been widely applied on pharmaceuticals, agrochemicals, and materials. The synthetic methodology for the introduction of fluorine into organic motifs has witnessed dramatically development recently. Selective C−F bond activation functionalization easily accessible fluorinated provided an efficient way to synthesize novel products degradate extremely stable pollutants. As photocatalytic transformations, light induced direct under mild conditions leading production various functionalities become one most advanced methodologies available. This minireview summarizes recent activations compounds, including fluoroarenes, gem ‐difluoroalkenes trifluoromethylarenes, intends illustrate readers a comprehensive this research topic via demonstrating representative examples detailed mechanism according reaction types transformations.

Language: Английский

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Solar Energy Catalysis

Angewandte Chemie, Journal Year: 2022, Volume and Issue: 134(29)

Published: April 26, 2022

Abstract When it comes to using solar energy promote catalytic reactions, photocatalysis technology is the first choice. However, sunlight can not only be directly converted into chemical through a photocatalytic process, also different energy‐transfer pathways. Using as source, reactions proceed independently, and coupled with other technologies enhance overall efficiency. Therefore, sunlight‐driven are diverse, need given specific definition. We propose timely perspective for driven by give them definition, namely “solar catalysis”. The concept of types catalysis, such photocatalysis, photothermal cell powered electrocatalysis, pyroelectric highlighted. Finally, their limitations future research directions discussed.

Language: Английский

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Photocatalytic α-arylation of cyclic ketones

Nature Synthesis, Journal Year: 2022, Volume and Issue: 1(2), P. 147 - 157

Published: Feb. 3, 2022

Language: Английский

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Visible Light‐Mediated Manipulation of 1,n‐Enynes in Organic Synthesis

ChemCatChem, Journal Year: 2022, Volume and Issue: 14(14)

Published: May 2, 2022

Abstract The 1, n ‐enynes are potent scaffolds in organic synthesis, providing a state‐of‐the‐art approach for synthesizing various acyclic and carbo‐ heterocyclic compounds. Radical cascade cyclization C−H functionalization of have gained immense attention the synthetic community. Significant advancement this field has been developed over years, employing harsh expensive metal catalysts usually associated with intense product purification unwanted side‐products. In context, advent visible light photocatalysis as mild efficient area is welcome step. Herein, we provide an exclusive overview recent developments light‐assisted manipulation ‐enynes. We classified review into 1,3‐, 1,4‐, 1,5‐, 1,6‐, 1,7‐, 1,8‐enynes, well dienyne, enediyne‐based reactions.

Language: Английский

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Visible light-assisted chemistry of vinyl azides and its applications in organic synthesis

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(23), P. 4723 - 4743

Published: Jan. 1, 2023

Vinyl azides have emerged as highly versatile precursors in organic synthesis due to their rich reactivity driven by the excellent leaving-group ability of molecular nitrogen. Over years, significant advancement has been achieved manipulation vinyl for construction C-C and C-X bonds. Typical methods involve application transition metals strong oxidants conversion into useful compounds employing harsh reaction conditions coupled with intense product purification. In this regard, visible light chemistry become one most exciting fields being mild, sustainable, often orthogonal conventional approaches. Visible light-induced reactions involving generate either 2H-azirines or iminyl radicals key intermediates, which may undergo further transformations form desired cyclic acyclic products. Herein, we provide synthetic transient intermediates biological significance under photocatalysis. We classified review two parts: (i) formation an radical intermediate (ii) 2H-azirine intermediate-based reactions.

Language: Английский

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