Recent advances in visible light-activated radical coupling reactions triggered by (i) ruthenium, (ii) iridium and (iii) organic photoredox agents

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(17), P. 9540 - 9685

Published: Jan. 1, 2021

Visible light-activated reactions continue to expand and diversify. The example shown here is a Birch reduction achieved by organophotoredox reagents.

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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Alkoxy Radicals See the Light: New Paradigms of Photochemical Synthesis

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 2429 - 2486

Published: Oct. 6, 2021

Alkoxy radicals are highly reactive species that have long been recognized as versatile intermediates in organic synthesis. However, their development has impeded due to a lack of convenient methods for generation. Thanks advances photoredox catalysis, enabling facile access alkoxy from bench-stable precursors and free alcohols under mild conditions, research interest this field renewed. This review comprehensively summarizes the recent progress radical-mediated transformations visible light irradiation. Elementary steps radical generation either or central reaction development; thus, each section is categorized discussed accordingly. Throughout review, we focused on different mechanisms well impact synthetic utilizations. Notably, catalytic abundant still early stage, providing intriguing opportunities exploit diverse paradigms.

Language: Английский

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Strategies to Generate Nitrogen-centered Radicals That May Rely on Photoredox Catalysis: Development in Reaction Methodology and Applications in Organic Synthesis

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 2353 - 2428

Published: Oct. 8, 2021

For more than 70 years, nitrogen-centered radicals have been recognized as potent synthetic intermediates. This review is a survey designed for use by chemists engaged in target-oriented synthesis. summarizes the recent paradigm shift access to and application of N-centered enabled visible-light photocatalysis. broadens streamlines approaches many small molecules because photocatalysis conditions are mild. Explicit attention paid innovative advances N–X bonds radical precursors, where X = Cl, N, S, O, H. clarity, key mechanistic data noted, available. Synthetic applications limitations summarized illuminate tremendous utility photocatalytically generated radicals.

Language: Английский

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Nitrogen-Centered Radicals in Functionalization of sp² Systems: Generation, Reactivity, and Applications in Synthesis

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(9), P. 8181 - 8260

Published: March 14, 2022

The chemistry of nitrogen-centered radicals (NCRs) has plentiful applications in organic synthesis, and they continue to expand as our understanding these reactive species increases. utility intermediates is demonstrated the recent advances C–H amination (di)amination alkenes. Synthesis previously challenging structures can be achieved by efficient functionalization sp2 moieties without prefunctionalization, allowing for faster more streamlined synthesis. This Review addresses generation, reactivity, application NCRs, including, but not limited to, iminyl, aminyl, amidyl, aminium species. Contributions from early discovery up most examples have been highlighted, covering radical initiation, thermolysis, photolysis, and, recently, photoredox catalysis. Radical-mediated intermolecular (hetero)arenes occur with a variety complex amine precursors, generating aniline derivatives, an important class drug development. Functionalization olefins achievable high anti-Markovnikov regioselectivity allows access difunctionalized when intermediate carbon are trapped. Additionally, reactivity NCRs harnessed rapid construction N-heterocycles such pyrrolidines, phenanthridines, quinoxalines, quinazolinones.

Language: Английский

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Bifunctional reagents in organic synthesis

Nature Reviews Chemistry, Journal Year: 2021, Volume and Issue: 5(5), P. 301 - 321

Published: April 12, 2021

Language: Английский

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Recent advances in visible-light photoredox-catalyzed nitrogen radical cyclization

Green Synthesis and Catalysis, Journal Year: 2020, Volume and Issue: 1(1), P. 42 - 51

Published: June 1, 2020

Visible-light photoredox catalysis is a powerful and attractive strategy for organic molecule activation new reaction design owing to its environmental-friendly characteristics unique catalytic mechanisms, has found wide applications in synthesis. This enables controllable generation of diverse nitrogen-centered radicals (NCRs) under mild conditions, providing access construction nitrogen-containing compounds. In this review, we critically illustrate the recent advances field visible-light photoredox-catalyzed cyclization radicals, based on different radical precursors modes. Wherever possible, particular emphasis also put working models synthetic applications.

Language: Английский

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Electrochemical generation of nitrogen-centered radicals for organic synthesis

Green Synthesis and Catalysis, Journal Year: 2021, Volume and Issue: 2(2), P. 165 - 178

Published: March 29, 2021

There is a resurgence of interests in organic electrochemistry, which generally accepted as green synthetic tool. In this context, many electrochemical methods have been developed the past decade to access various nitrogen-centered radicals (NCRs) from readily available precursors controlled fashion, enabling rapid development NCR-mediated new reactions for construction nitrogen-containing compounds. review, recent advances chemistry electrochemically generated NCRs are critically highlighted, based on strategies their formation and types NCRs. Focus put mechanism generation different applications.

Language: Английский

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Photoinduced Copper-Catalyzed Asymmetric C–O Cross-Coupling

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(33), P. 13382 - 13392

Published: Aug. 10, 2021

The construction of carbon–heteroatom bonds is one the most active areas research in organic chemistry because function molecules often derived from presence heteroatoms. Although considerable advances have recently been achieved radical-involved catalytic asymmetric C–N bond formation, there has little progress corresponding C–O bond-forming processes. Here, we describe a photoinduced copper-catalyzed cross-coupling readily available oxime esters and 1,3-dienes to generate diversely substituted allylic with high regio- enantioselectivity (>75 examples; up 95% ee). reaction proceeds at room temperature under excitation by purple light-emitting diodes (LEDs) features use single, earth-abundant copper-based chiral catalyst as both photoredox for radical generation source induction coupling. Combined experimental density functional theory (DFT) computational studies suggest formation π-allylcopper complexes redox-active bifunctional reagents through radical–polar crossover process.

Language: Английский

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

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(14), P. 7873 - 7879

Published: Jan. 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.

Language: Английский

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