Recent Advances in Employing Catalytic Donors and Acceptors in Electron Donor–Acceptor Complex Photochemistry

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(16), P. 10555 - 10563

Published: July 29, 2022

Electron donor–acceptor (EDA) complexes provide a means to initiate radical reactions under visible light irradiation using substrates that do not absorb individually. Catalytic approaches complex formation are vital for advancing this synthetic strategy as it decouples the complexation and photogeneration of radicals from substrate functionalization, limitation inherent stoichiometric restricts structural diversity. This Synopsis highlights recent developments in EDA photochemistry which either donor or acceptor employed catalytically.

Language: 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, Journal Year: 2023, Volume and Issue: 14(21), P. 5545 - 5568

Published: Jan. 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.

Language: Английский

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Radical Perfluoroalkylation of Aliphatic Substrates

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(12), P. 7756 - 7794

Published: May 25, 2023

A selection of perfluoroalkylation reactions aliphatic substrates that display methodological and synthetic amplitude will be studied, giving examples their applications mechanistic details. An array approaches for fluoroalkylation are documented; in particular, radical protocols prominent among methods. To effect, addition perfluoroalkyl radicals RF (RF=CnF2n+1, n > 1) to unsaturated organic serve as one the most direct efficacious ways access fluoroalkylated scaffolds. The syntheses perfluoroalkyl-substituted vinyl, alkynyl, allylic compounds; hydro-, iodo-, oxy-perfluoroalkylated alkanes olefins; carbonyl enamides, amides, thioamides, hydrazones; multicomponent studied. While there a number accomplished reports on organofluorination, we aim provide an overview radical-involved substrates, covering from 2018 early 2023, summarized Tables 1–4.

Language: Английский

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Triarylamines as catalytic donors in light-mediated electron donor–acceptor complexes

Chemical Science, Journal Year: 2023, Volume and Issue: 14(13), P. 3470 - 3481

Published: Jan. 1, 2023

Recently, photochemistry of Electron Donor-Acceptor (EDA) complexes employing catalytic amounts electron donors have become interest as a new methodology in the catalysis field, allowing for decoupling transfer (ET) from bond-forming event. However, examples practical EDA systems regime remain scarce, and their mechanism is not yet well-understood. Herein, we report discovery an complex between triarylamines α-perfluorosulfonylpropiophenone reagents, catalyzing C-H perfluoroalkylation arenes heteroarenes under visible light irradiation pH- redox-neutral conditions. We elucidate this reaction using detailed photophysical characterization complex, resulting triarylamine radical cation, its turnover

Language: Английский

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Phenanthroline-Initiated Anti-selective Hydrosulfonylation of Unactivated Alkynes with Sulfonyl Chlorides

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(10), P. 6983 - 6993

Published: May 8, 2023

A simple and general method for anti-selective hydrosulfonylation of unactivated alkynes with sulfonyl chlorides in the presence a catalytic amount phenanthroline-based Lewis base (Me3Si)3SiH as hydrogen atom donor has been developed. The protocol proceeds efficiently under mild metal-free conditions, delivering diverse set (Z)-vinyl sulfones high stereoselectivity. Additionally, displays excellent functional-group compatibility can be applied to late-stage modifications complex drugs their derivatives. Experimental density functional theory studies unveiled that key transformation's success is employment base, which interacts form halogen-bond accelerates cleavage S–Cl bonds irradiation visible light.

Language: Английский

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Photochemical Synthesis of Lactones, Cyclopropanes and ATRA Products: Revealing the Role of Sodium Ascorbate**

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: unknown

Published: Feb. 7, 2024

Abstract Light‐mediated processes have received significant attention, since they re‐surfaced unconventional reactivity platforms, complementary to conventional polar chemistry. γ‐Lactones and cyclopropanes are prevalent moieties, found in numerous natural products pharmaceuticals. Among various methods for their synthesis, light‐mediated protocols coming the spotlight, although these contingent upon use of photoorgano‐ or metal‐based catalysts. Herein, we introduce a novel photochemical activation iodo‐reagents via cheap sodium ascorbate ascorbic acid enable homolytic scission addition onto double bonds. The developed protocol was applied successfully formal [3+2] cycloaddition synthesis γ‐lactones, traditional atom transfer radical (ATRA) reactions one‐pot two‐step conversion alkenes cyclopropanes. In all cases, desired were obtained good high yields, while reaction mechanism thoroughly investigated. Depending on nature iodo‐reagent, halogen hydrogen‐bonded complex is formed, which initiates process.

Language: Английский

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The synergism of sequential paired electrosynthesis with halogen bonding activation for the cyclization of organochlorides with olefins

Science China Chemistry, Journal Year: 2022, Volume and Issue: 66(2), P. 540 - 547

Published: Dec. 14, 2022

Language: Английский

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Direct Perfluoroalkylation of C−H Bonds in (Hetero)arenes

Chemistry - A European Journal, Journal Year: 2022, Volume and Issue: 28(41)

Published: May 11, 2022

Abstract Perfluoroalkylated (hetero)arenes represent an extremely important family of molecules commonly utilized in many areas such as medicinal chemistry, agrochemistry and material sciences. Due to their unique properties, they have attracted significant interest from synthetic chemists various methods been developed for synthesis. Among them, the direct perfluoroalkylation C(sp 2 )−H bonds is one most attractive straightforward ones, provided that it proceeds with high levels regioselectivity. In this review article, a comprehensive overview advances field presented, special focus on reaction mechanisms involved these transformations All available classified according nature perfluoroalkyl chain introduced, trifluoromethylation reactions being overviewed separate section, reagents/catalysts required.

Language: Английский

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A Pyridine-Based Donor–Acceptor Molecule: A Highly Reactive Organophotocatalyst That Enables the Reductive Cleavage of C–Br Bonds through Halogen Bonding

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(13), P. 7843 - 7849

Published: June 17, 2022

We report a pyridine-based donor–acceptor molecule that exhibits high reactivity as visible-light photoredox catalyst. This catalyst enables the formation of radicals from alkyl bromides, which are useful radical precursors unfortunately do not perform well under reductive conditions, by direct, photocatalytic cleavage C–Br bond. A wide variety bromides including unactivated ones can be used ambient conditions without any additional activating agents to give C–C coupling products in good yield. Mechanistic studies indicated photocatalyst interacts with through halogen bonding and pyridine moiety is important for progress reaction.

Language: Английский

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Principles and Applications of CF₂X Moieties as Unconventional Halogen Bond Donors in Medicinal Chemistry, Chemical Biology, and Drug Discovery

Journal of Medicinal Chemistry, Journal Year: 2023, Volume and Issue: 66(15), P. 10202 - 10225

Published: July 24, 2023

As an orthogonal principle to the established (hetero)aryl halides, we herein highlight usefulness of CF2X (X = Cl, Br, or I) moieties. Using tool compounds bearing moieties, study their chemical/metabolic stability and logP/solubility, as well role XB in small molecular crystal structures. Employing QM techniques, analyze observed interactions, provide insights into conformational flexibilities preferences potential interaction space. For application design, characterize donor capacities its strength dependent on geometric parameters. Implementation acetamides our HEFLibs biophysical evaluation (STD-NMR/ITC), followed by X-ray analysis, reveals a highly interesting binding mode for fragment 23 JNK3, featuring CF2Br toward P-loop, chalcogen bonds. We suggest that underexplored chemical space combined with unconventional modes provides excellent opportunities patentable chemotypes therapeutic intervention.

Language: Английский

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