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

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 2752 - 2906

Published: Aug. 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.

Language: Английский

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Photocatalytic Late-Stage C–H Functionalization

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(8), P. 4237 - 4352

Published: Jan. 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.

Language: Английский

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Chiral Photocatalyst Structures in Asymmetric Photochemical Synthesis

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 1654 - 1716

Published: Oct. 4, 2021

Asymmetric catalysis is a major theme of research in contemporary synthetic organic chemistry. The discovery general strategies for highly enantioselective photochemical reactions, however, has been relatively recent development, and the variety photoreactions that can be conducted stereocontrolled manner consequently somewhat limited. photocatalysis complicated by short lifetimes high reactivities characteristic photogenerated reactive intermediates; design catalyst architectures provide effective enantiodifferentiating environments these intermediates while minimizing participation uncontrolled racemic background processes proven to key challenge progress this field. This review provides summary chiral structures have studied solution-phase asymmetric photochemistry, including sensitizers, inorganic chromophores, soluble macromolecules. While some photocatalysts are derived from privileged both ground-state transformations, others structural designs unique offer insight into logic required photocatalysis.

Language: Английский

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Enantioselective Radical Reactions Using Chiral Catalysts

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(6), P. 5842 - 5976

Published: Jan. 24, 2022

Benefiting from the impressive increase in fundamental knowledge, last 20 years have shown a continuous burst of new ideas and consequently plethora catalytic methods for enantioselective radical reactions. This review aims to provide complete survey progress achieved over this latter period. The first part focuses on use chiral organocatalysts, these include catalysts covalently linked substrate those that interact with by weaker interactions like hydrogen bonds. second is devoted transition-metal redox catalysis which organized according increasing atomic number first-row transition metals (Ti, Cr, Fe, Mn, Co, Ni, Cu). Bioinspired manganese- iron-mediated hydroxylations oxidations are also discussed. A specific section dedicated reactivity Ru, Rh, Ir complexes as Lewis acids special focus at metal. Absorption photons result different events such energy transfer, single-electron hydrogen-atom transfer facilitating formation radicals. Organocatalysis has been successfully combined photocatalysts, opened pathways enlarging precursors available. merger photocatalysis organo- or metalla-photocatalysis brought novelty allowed discovery large original transformations. enzyme-catalyzed reactions involving intermediates largely benefit visible-light irradiation included review. provides comprehensive inventory goal detailing reaction mechanisms involved transformations any nonspecialist could find their own creativity invent yet unknown applications.

Language: Английский

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Recent Progress and Prospects in Catalytic Water Treatment

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(3), P. 2981 - 3121

Published: Dec. 7, 2021

Presently, conventional technologies in water treatment are not efficient enough to completely mineralize refractory contaminants. In this context, the implementation of catalytic processes could be an alternative. Despite advantages provided terms kinetics transformation, selectivity, and energy saving, numerous attempts have yet led at industrial scale. This review examines investigations different scales for which controversies limitations must solved bridge gap between fundamentals practical developments. Particular attention has been paid development solar-driven some other emerging processes, such as microwave assisted catalysis, plasma-catalytic or biocatalytic remediation, taking into account their specific drawbacks. Challenges a better understanding related complexity systems coexistence various solid-liquid-gas interfaces identified.

Language: Английский

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Urea as a Redox-Active Directing Group under Asymmetric Photocatalysis of Iridium-Chiral Borate Ion Pairs

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(46), P. 19462 - 19467

Published: Nov. 5, 2020

The development of a photoinduced, highly diastereo- and enantioselective [3 + 2]-cycloaddition N-cyclopropylurea with α-alkylstyrenes is reported. This asymmetric radical cycloaddition relies on the strategic placement urea cyclopropylamine as redox-active directing group (DG) anion-binding ability use an ion pair, comprising iridium polypyridyl complex weakly coordinating chiral borate ion, photocatalyst. structure anion component catalyst governs reactivity, pertinent structural modification enables high levels catalytic activity stereocontrol. system tolerates range hence offers rapid access to various aminocyclopentanes contiguous tertiary quaternary stereocenters, DG readily removable.

Language: Английский

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Asymmetric Photocatalysis Enabled by Chiral Organocatalysts

ChemCatChem, Journal Year: 2021, Volume and Issue: 14(1)

Published: Oct. 21, 2021

Abstract Visible‐light photocatalysis has advanced as a versatile tool in organic synthesis. However, attaining precise stereocontrol photocatalytic reactions been longstanding challenge due to undesired photochemical background and the involvement of highly reactive radicals or radical ion intermediates generated under conditions. To address this problem expand synthetic utility reactions, number innovative strategies, including mono‐ dual‐catalytic approaches, have recently emerged. Of these, exploiting chiral organocatalysis, such enamine catalysis, iminium‐ion Brønsted acid/base N ‐heterocyclic carbene induce chirality transfer widely explored. This Review aims provide current, comprehensive overview asymmetric enabled by organocatalysts published through June 2021. The substrate scope, advantages, limitations, proposed reaction mechanisms each are discussed. review should serve reference for development visible‐light‐induced promote improvement chemical reactivity stereoselectivity these reactions.

Language: Английский

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Access to chiral β-sulfonyl carbonyl compounds via photoinduced organocatalytic asymmetric radical sulfonylation with sulfur dioxide

Chemical Science, Journal Year: 2022, Volume and Issue: 13(30), P. 8834 - 8839

Published: Jan. 1, 2022

An organocatalytic enantioselective radical reaction of potassium alkyltrifluoroborates, DABCO·(SO

Language: Английский

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Supramolecular Engineering and Self-Assembly Strategies in Photoredox Catalysis

ACS Catalysis, Journal Year: 2020, Volume and Issue: 11(2), P. 710 - 733

Published: Dec. 31, 2020

Visible-light-mediated photoredox catalysis has evolved as an efficient and mild alternative to conventional organic synthesis. Inspired by the elegance sophistication of natural photosynthetic machinery involving complex self-assembled systems, recently researchers have resorted implementation supramolecular chemistry in catalytic processes with objective achieving improved efficiency for known chemical reactions, well developing advanced methodologies inaccessible transformations. Supramolecular engineering offers ability customize existing properties traditional catalysts various self-assembly strategies expands their scope cutting-edge synthetic means noncovalent interactions different components. In this review, we summarize recent advances key achievements synthesis adopting techniques based on systems underline advantages mechanistic facets. Diverse directional interaction driven are thoroughly discussed. Furthermore, photocatalytic reactions within confined nanospaces (viz. micelles, vesicles, polymersomes, polymeric nanoparticles, gels etc.) summarized. Finally, a brief perspective encouraging future prospects challenges contemporary field is presented.

Language: Английский

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Visible-Light-Activated Asymmetric Addition of Hydrocarbons to Pyridine-Based Ketones

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(9), P. 5136 - 5144

Published: April 15, 2022

Enantioselective photoreduction of ketones with hydrocarbons is promising for the straightforward construction chiral tertiary alcohols. But it generally promoted by ultraviolet light via ketyl radical–alkyl radical coupling, which suffers from a competitive charge-transfer process and self/cross coupling reactions. An appropriate selection catalyst that can alter reaction pathway deliver spatial required. Accordingly, we disclosed combined system involving Er(III)-based Lewis acid catalysis, Ir(III)-based photoredox bromide-radical-mediated hydrogen atom transfer. The introduction bulky nonredox through enables addition inhibits above visible-light-promoted catalytic asymmetric alkylation heteroaryl-based diverse (mainly benzyl) delivered variety congested enantioenriched alcohols (up to 97% yield, 96% enantiomeric excess (ee)).

Language: Английский

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