Carbon-to-nitrogen single-atom transmutation of azaarenes

Nature, Journal Year: 2023, Volume and Issue: 623(7985), P. 77 - 82

Published: Nov. 1, 2023

Language: Английский

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Palladium Hydride-Enabled Hydroalkenylation of Strained Molecules

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(45), P. 20875 - 20883

Published: Oct. 31, 2022

We report the first palladium hydride enabled hydroalkenylation of strained molecules. This new mild protocol proceeds via a regio- and chemoselective hydropalladation step, followed by photoinduced radical alkyl Heck reaction. methodology represents reactivity mode for molecules opens avenues catalysis. The reaction is compatible with wide range functional groups can be applied to complex structures, delivering diverse array highly valuable modifiable alkenylated cyclobutanes cyclopropanes. A hydroalkenylation/diastereoselective rearrangement cascade toward cyclopentene scaffold has also been demonstrated.

Language: Английский

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Anaerobic Hydroxylation of C(sp³)–H Bonds Enabled by the Synergistic Nature of Photoexcited Nitroarenes

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(5), P. 2794 - 2799

Published: Jan. 25, 2023

A photoexcited-nitroarene-mediated anaerobic C-H hydroxylation of aliphatic systems is reported. The success this reaction due to the bifunctional nature photoexcited nitroarene, which serves as bond activator and oxygen atom source. Compared previous methods, approach cost- atom-economical commercial availability sole mediator reaction. Because conditions transformation, a noteworthy expansion in substrate scope can be obtained compared prior reports. Mechanistic studies support that nitroarenes engage successive hydrogen transfer radical recombination events with hydrocarbons, leading N-arylhydroxylamine ether intermediates. Spontaneous fragmentation these intermediates leads key products.

Language: Английский

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Carbon–Carbon Bond Cleavage for Late-Stage Functionalization

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(22), P. 12313 - 12370

Published: Nov. 9, 2023

Late-stage functionalization (LSF) introduces functional group or structural modification at the final stage of synthesis natural products, drugs, and complex compounds. It is anticipated that late-stage would improve drug discovery's effectiveness efficiency hasten creation various chemical libraries. Consequently, products a productive technique to produce product derivatives, which significantly impacts biology development. Carbon-carbon bonds make up fundamental framework organic molecules. Compared with carbon-carbon bond construction, activation can directly enable molecular editing (deletion, insertion, atoms groups atoms) provide more efficient accurate synthetic strategy. However, selective unstrained still one most challenging projects in synthesis. This review encompasses strategies employed recent years for cleavage by explicitly focusing on their applicability functionalization. expands current discourse reactions providing comprehensive overview types bonds. includes C-C(sp), C-C(sp2), C-C(sp3) single bonds; double triple bonds, focus catalysis transition metals organocatalysts. Additionally, specific topics, such as ring-opening processes involving three-, four-, five-, six-membered rings, are discussed, exemplar applications these techniques showcased context bioactive molecules discovery. aims shed light advancements field propose potential avenues future research realm

Language: Английский

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Synthesis of polysubstituted azepanes by dearomative ring expansion of nitroarenes

Nature Chemistry, Journal Year: 2024, Volume and Issue: 16(5), P. 771 - 779

Published: Jan. 25, 2024

Language: Английский

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Red-Light-Based Effective Photocatalysis of a Photosensitive Covalent Organic Framework Triggered Singlet Oxygen

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(4), P. 2631 - 2641

Published: Feb. 6, 2024

The direct application of low-energy red light for photochemical transformations is synthetically appealing but practically challenging. Covalent organic frameworks (COFs) exhibit significant potential within this domain, owing to their broad spectrum absorption and prevalence in reactions, despite the fact that these photocatalysts are now mainly focused on using ultraviolet (UV) blue light. In study, an imidazole-linked porphyrin-based COF, PyPor-COF, which exhibits a wide band ranging from 200 700 nm, especially strong 630 expected be applied photocatalytic reactions. PyPor-COF possesses capacity selectively generate singlet oxygen (1O2) with high efficiency, renders it efficient photosensitizer reactions olefin cleavages thioanisole photooxidation under present study demonstrates intriguing prospect photoactive COFs as type II utilization photocatalyses.

Language: Английский

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Characterization of A π–π stacking cocrystal of 4-nitrophthalonitrile directed toward application in photocatalysis

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Feb. 16, 2024

Abstract Photoexcitation of the electron-donor-acceptor complexes have been an effective approach to achieve radicals by triggering electron transfer. However, catalytic version complex photoactivation is quite underdeveloped comparing well-established utilization electronically biased partners. In this work, we utilize 4-nitrophthalonitrile as acceptor facilitate efficient π-stacking with electron-rich aromatics form complex. The characterization and energy profiles on cocrystal 1,3,5-trimethoxybenzene disclose that transfer highly favorable under light irradiation. This catalyst can be efficiently applied in benzylic C−H bond developing Giese reaction alkylanisoles oxidation benzyl alcohols. A broad scope tolerated a mechanism also proposed. Moreover, corresponding π-anion interaction potassium formate further hydrocarboxylation alkenes efficiently.

Language: Английский

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Recent Advances in C–H Functionalisation through Indirect Hydrogen Atom Transfer

Molecules, Journal Year: 2023, Volume and Issue: 28(16), P. 6127 - 6127

Published: Aug. 18, 2023

The functionalisation of C–H bonds has been an enormous achievement in synthetic methodology, enabling new retrosynthetic disconnections and affording simple equivalents for synthons. Hydrogen atom transfer (HAT) is a key method forming alkyl radicals from substrates. Classic reactions, including the Barton nitrite ester reaction Hofmann–Löffler–Freytag reaction, among others, provided early examples HAT. However, recent developments photoredox catalysis electrochemistry have made HAT powerful tool capable introducing wide range functional groups into bonds. Moreover, greater mechanistic insights stimulated development increasingly site-selective protocols. Site-selectivity can be achieved through tuning electron density at certain using additives, judicious choice reagent, solvent system. Herein, we describe latest methods functionalizing C–H/Si–H/Ge–H indirect between 2018–2023, as well critical discussion reagents, aspects, substrate scopes, background contexts

Language: Английский

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Aziridination via Nitrogen-Atom Transfer to Olefins from Photoexcited Azoxy-Triazenes

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(14), P. 9499 - 9505

Published: March 24, 2024

Herein, we report that readily accessible azoxy-triazenes can serve as nitrogen atom sources under visible light excitation for the phthalimido-protected aziridination of alkenes. This approach eliminates need external oxidants, precious transition metals, and photocatalysts, marking a departure from conventional methods. The versatility this transformation extends to selective both activated unactivated multisubstituted alkenes varying electronic profiles. Notably, process avoids formation competing C–H insertion products. described protocol is operationally simple, scalable, adaptable photoflow conditions. Mechanistic studies support idea photofragmentation results in generation free singlet nitrene. Furthermore, mild photoredox-catalyzed N–N cleavage protecting group furnish aziridines reported. Our findings contribute advancement sustainable practical methodologies synthesis nitrogen-containing compounds, showcasing potential broader applications synthetic chemistry.

Language: Английский

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Selective Upcycling of Polyolefins into High-Value Nitrogenated Chemicals

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 6, 2024

The selective upcycling of polyolefins to create products increased value has emerged as an innovative approach carbon resource stewardship, drawing significant scientific and industrial interest. Although recent advancements in recycling technology have facilitated the direct conversion hydrocarbons or oxygenated compounds, synthesis nitrogenated compounds from such waste not yet been disclosed. Herein, we demonstrate a novel for by efficiently transforming range postconsumer plastic into nitriles amides. This process leverages catalytic properties manganese dioxide combination with inexpensive nitrogen source, urea, make it both practical economically viable. Our only opens new avenues creation chemicals polyolefin but also underscores critical importance valorizing resources originally derived fossil fuels. study provides strategy sustainable polyolefins.

Language: Английский

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