Merging Photoinduced Electron Transfer with Hydrogen Atom Transfer: Formal β-C(sp³)–H Pyridination of Carbonyls

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 9, 2025

In this study, a novel approach that combines photoinduced electron transfer (ET) with hydrogen atom (HAT) has been introduced for the selective β-C(sp3)–H pyridination of carbonyl compounds. This method is notable its absence transition metals and ability to function under benign reaction conditions, resulting in range pyridinated derivatives consistently moderate good yields. The significance technique further underscored by potential late-stage functionalization pharmaceutically significant molecules. Mechanistic investigations confirmed proceeds via radical-mediated pathway.

Language: Английский

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Visible-Light-Induced Divergent C–H Esterification/Alkylation of Quinoxalin-2(1H)-ones with Aldehydes under Mild Conditions

Organic Letters, Journal Year: 2025, Volume and Issue: 27(10), P. 2526 - 2531

Published: March 5, 2025

Herein, we introduce an efficient and straightforward strategy for the selective C-H esterification alkylation of quinoxalin-2(1H)-ones with aldehydes. A key feature our study is ability to perform both using different types The reaction system highly compatible a range aldehydes, yielding C3-esterified C3-alkylated products in moderate-to-good yields. applicability this approach further enhanced by its scalability through continuous-flow synthesis, late-stage modification significant molecules, product derivatization. Our mechanistic investigations reveal radical relay mechanism, triggered hydrogen atom transfer process.

Language: Английский

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Photocatalytic acceptorless dehydrogenation of flavanones by cationic Eosin Y as a bifunctional catalyst

Organic & Biomolecular Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

We report the first example of photocatalytic acceptorless dehydrogenation using cationic Eosin Y as a bifunctional photocatalyst, without metal catalysts or HAT reagents.

Language: Английский

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Ni-catalysed acceptorless dehydrogenative aromatisation of cyclohexanones enabled by concerted catalysis specific to supported nanoparticles

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Feb. 7, 2025

The dehydrogenative aromatisation of cyclohexanone derivatives has had a transformative influence on the synthesis aromatic compounds because functional groups can be easily introduced at desired positions via classic organic reactions without being limited by ortho-, meta- or para-orientations. However, research is still acceptorless aromatisation, especially with regard to nonprecious-metal catalysts. Ni promising candidate catalyst as congener Pd, but thermally Ni-catalysed not been reported even in an oxidative manner difficulty β-hydride elimination and fast re-insertion Ni–H species. Here, we report CeO2-supported Ni(0) nanoparticle for derivatives. This widely applicable various such cyclohexanols, cyclohexylamines, N-heterocycles, enamines β-heteroatom-substituted ketones. Through experiments, demonstrate that present reaction was achieved concerted catalysis utilizing metal ensembles unique supported Acceptorless aromatization cyclohexanones advantageous nickel study presents method broad substrate applicability, nanoparticles.

Language: Английский

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Harnessing Nitroarenes: Photo-Driven Synergistic Construction of Phosphinic Amides via Hydrogen Transfer and Oxygen Migration

Chemical Communications, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

A method for synthesizing phosphinic amides via hydrogen transfer and oxygen migration through an EDA complex-based cascade reaction is presented.

Language: Английский

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Tandem Azolation/Aromatization of Tetrahydronaphthalenes with Hydrogen Evolution via Organophotoredox/Cobalt Dual Catalysis

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: March 27, 2025

Reported herein is a photoredox/cobaloxime dual-catalytic approach to execute tandem dehydrogenative azolation and aromatization of tetrahydronaphthalene for rapid construction N-(β-naphthyl)azole architectures. This protocol highlights noble metal-free external oxidants-free conditions, step- atom-economy, site-selectivity. A preliminary mechanistic study has uncovered that the transformation undergoes N-centered radical mediated C–H/N–H cross-coupling followed by saturated naphthyl surrogates under visible light irradiation, DFT calculations elucidate

Language: Английский

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Light-fuelled nitro-reduction via cascaded electron donor-acceptor complexes in aqueous media

Green Chemistry, Journal Year: 2024, Volume and Issue: 26(18), P. 9682 - 9689

Published: Jan. 1, 2024

Developed herein is a metal-free method for nitro reduction via cascade electron donor acceptor complex photoexcitation in aqueous media.

Language: Английский

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Photo-driven reduction/cyclization of nitroarenes via electron donor-acceptor complexes: a novel acquisition for N-heterocycles

Green Chemistry, Journal Year: 2024, Volume and Issue: 26(23), P. 11531 - 11539

Published: Jan. 1, 2024

An EDA complex-based method for the reduction/cyclization of nitroarenes to obtain N -heterocycles with H 2 O as a clean by-product is presented.

Language: Английский

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Biomimetic Dehydrogenative Intermolecular Formal Allylic Amidation of Branched α‐Olefins

Advanced Science, Journal Year: 2024, Volume and Issue: 12(2)

Published: Nov. 18, 2024

Abstract Allylic amide moieties are commonly encountered in natural products and privileged structures pharmaceuticals agrochemicals. Moreover, because allylic can be to converted into an array of high‐value motifs, they have been widely employed organic synthesis. However, the development catalytic systems for intermolecular amidation olefins, particularly branched α ‐olefins, has proven challenging. Here, a biomimetic, synergistic method is reported that combines photoredox, cobalt, Brønsted base catalysis synthesis substituted amides from ‐olefins simple imides without using oxidants. This low‐cost, operationally features broad substrate scope excellent functional group compatibility. it successfully used functionalization several structurally complex molecules demonstrating method's potential utility medicinal chemistry applications. Mechanistic studies revealed C( sp 3 )─N bond formation mediated by nitrogen‐centered radical intermediate, which generated via sequence involving deprotonation single‐electron oxidation.

Language: Английский

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Iron-Catalyzed One-Pot Cascade Reactions of Oximes with Inactivated Saturated Ketones: Entry to Highly Substituted Pyridines

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 7, 2024

An iron-catalyzed oxidative [3 + 3] annulation of oxime esters with inactivated saturated ketones is described. This cascade strategy allows one-step rapid synthesis various structurally important pyridines through an dehydrogenation/annulation/oxidative aromatization sequence via direct α,β-dehydrogenation simple followed by oximes. method shows good functional group tolerance, readily accessible starting materials, a wide substrate scope, high chemoselectivity, and no need for extra stoichiometric oxidant also applicable to the late-stage functionalization natural products.

Language: Английский

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