Contemporary methods for generation of aryl radicals

Chemical Society Reviews, Год журнала: 2020, Номер 50(4), С. 2244 - 2259

Опубликована: Дек. 14, 2020

The synthetic utility of aryl radicals has been established in the last century, however, their broad applications were hampered by ineffective generation methods. It was decade, that a rapid development various redox systems took place, thus triggering renaissance radical chemistry. This tutorial review focuses on start-of-the-art methods for radicals. Primarily, light-induced systems, including photoredox catalysis, visible light transition metal and chemistry electron donor-acceptor complexes, are reviewed. main current precursors evaluated together with selected examples modern applications.

Язык: Английский

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A General Organocatalytic System for Electron Donor–Acceptor Complex Photoactivation and Its Use in Radical Processes

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(31), С. 12304 - 12314

Опубликована: Июль 28, 2021

We report herein a modular class of organic catalysts that, acting as donors, can readily form photoactive electron donor-acceptor (EDA) complexes with variety radical precursors. Excitation visible light generates open-shell intermediates under mild conditions, including nonstabilized carbon radicals and nitrogen-centered radicals. The nature the commercially available xanthogenate dithiocarbamate anion organocatalysts offers versatile EDA complex catalytic platform for developing mechanistically distinct reactions, encompassing redox-neutral net-reductive processes. Mechanistic investigations, by means quantum yield determination, established that closed cycle is operational all developed processes, highlighting ability to turn over iteratively drive every cycle. also demonstrate how catalysts' stability method's high functional group tolerance could be advantageous direct functionalization abundant groups, aliphatic carboxylic acids amines, applications in late-stage elaboration biorelevant compounds enantioselective catalysis.

Язык: Английский

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Aryl Transfer Strategies Mediated by Photoinduced Electron Transfer

Chemical Reviews, Год журнала: 2021, Номер 122(2), С. 2695 - 2751

Опубликована: Окт. 21, 2021

Radical aryl migrations are powerful techniques to forge new bonds in aromatic compounds. The growing popularity of photoredox catalysis has led an influx novel strategies initiate and control migration starting from widely available radical precursors. This review encapsulates progress enabled by photochemical methods─particularly catalysis─since 2015. Special attention is paid descriptions scope, mechanism, synthetic applications each method.

Язык: Английский

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Direct excitation strategy for radical generation in organic synthesis

Chemical Society Reviews, Год журнала: 2021, Номер 50(11), С. 6320 - 6332

Опубликована: Янв. 1, 2021

This tutorial review encompasses the radical generation based on classical methods and photoredox catalysis. It will also focus only demanding visible-light, which involves EDA complex direct photo-excitation strategy.

Язык: Английский

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Visible‐Light‐Induced 1,3‐Aminopyridylation of [1.1.1]Propellane with N‐Aminopyridinium Salts

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(14), С. 7873 - 7879

Опубликована: Янв. 7, 2021

Through the formation of an electron donor-acceptor (EDA) complex, strain-release aminopyridylation [1.1.1]propellane with N-aminopyridinium salts as bifunctional reagents enabled direct installation amino and pyridyl groups onto bicyclo[1.1.1]pentane (BCP) frameworks in absence external photocatalyst. The robustness this method to synthesize 1,3-aminopyridylated BCPs under mild metal-free conditions is highlighted by late-stage modification structurally complex biorelevant molecules. Moreover, strategy was extended P-centered CF3 radicals for unprecedented incorporation such functional pyridine across BCP core a three-component coupling. This practical lays foundation straightforward construction new valuable C4-pyridine-functionalized chemical entities, thus significantly expanding range accessibility BCP-type bioisosteres applications drug discovery.

Язык: Английский

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A general arene C–H functionalization strategy via electron donor–acceptor complex photoactivation

Nature Chemistry, Год журнала: 2022, Номер 15(1), С. 43 - 52

Опубликована: Дек. 5, 2022

Язык: Английский

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Photobiocatalysis for Abiological Transformations

Accounts of Chemical Research, Год журнала: 2022, Номер 55(8), С. 1087 - 1096

Опубликована: Март 30, 2022

Harnessing biocatalysts for novel abiological transformations is a longstanding goal of synthetic chemistry. Combining the merits biocatalysis and photocatalysis allows selective fueled by visible light offers many advantages including new reactivity, high enantioselectivity, greener syntheses, yields. Photoinduced electron or energy transfer enables methodologies that complement conventional two processes offer orthogonal pathways developing reactions. Enzymes are well suited can be tuned directed evolution to exert control over open-shell intermediates, thereby suppressing undesirable reactions delivering chemo- stereoselectivities. Within past decade, combination was mainly focused on exploiting light-regenerated cofactors function native enzymatic activity. However, recent developments have demonstrated unlock new-to-nature Particularly, discovery application strategies poised expand applications photobiocatalysis.In five years, our lab has been studying combinations applied create solve challenges in organic Our efforts expanded combining external photocatalysts with enzymes through construction synergistic cooperative stereoconvergent reduction system consisting photosensitized ene-reductase-catalyzed alkene reduction. Additionally, also extended capability cofactor-dependent photoenzymatic systems include enantioselective bimolecular radical hydroalkylations alkenes irradiating donor-acceptor complexes comprised redox active unnatural substrates.In this Account, we highlight developed group others aim introducing non-natural reactivity enzymes. Presently, achieve repurposing natural photoenzymes, elucidation photoreactivity within enzymes, artificial photoenzymes. By demonstrating successful these achieving transformations, hope spur interest expanding scope photobiocatalytic use extension creation strategies. elucidate intuition synergizing unique capabilities so photobiocatalysis recognized as potential solution difficult

Язык: Английский

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Sustainable Thioetherification via Electron Donor–Acceptor Photoactivation Using Thianthrenium Salts

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(22)

Опубликована: Март 16, 2022

Abstract The synthesis of sulfides has been widely studied because this functional subunit is prevalent in biomolecules and pharmaceuticals, as well being a useful synthetic platform for further elaboration. Thus, various methods to build C−S bonds have developed, but typically they require the use precious metals or harsh conditions. Electron donor–acceptor (EDA) complex photoactivation strategies emerged versatile sustainable ways achieve bond formation, avoiding challenges associated with previous methods. This work describes an open‐to‐air, photoinduced, site‐selective C−H thioetherification from readily available reagents via EDA formation that tolerates wide range different groups. Moreover, C(sp 2 )−halogen remain intact using protocol, allowing late‐stage installation sulfide motif bioactive scaffolds, while yet modification through more traditional C−X cleavage protocols. Additionally, mechanistic investigations support envisioned scenario.

Язык: Английский

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Strain-Release Photocatalysis

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(38), С. 20716 - 20732

Опубликована: Сен. 15, 2023

The concept of strain in organic compounds is as old modern chemistry and was initially introduced to justify the synthetic setbacks along synthesis small ring systems (pars construens strain). In last decades, chemists have developed an arsenal strain-release reactions destruens strain) which can generate─with significant driving force─rigid aliphatic that act three-dimensional alternatives (hetero)arenes. Photocatalysis added additional dimension processes by leveraging energy photons create chemical complexity under mild conditions. This perspective presents latest advancements photocatalysis─with emphases on mechanisms, catalytic cycles, current limitations─the unique architectures be produced, possible future directions.

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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