Synthesis of Diverse 4‐Pyrrolin‐2‐ones by Electrochemically Induced Dehydrogenative Regioselective Cyclization of 3‐Aza‐1,5‐dienes and 1,3‐Dicarbonyl Compounds

European Journal of Organic Chemistry, Год журнала: 2024, Номер 27(11)

Опубликована: Янв. 20, 2024

Abstract A practical and mild electrochemical dehydrogenative regioselective cyclization method has been established for the synthesis of 4‐pyrrolin‐2‐ones using 3‐aza‐1,5‐dienes 1,3‐dicarbonyl compounds as substrates. This protocol is catalyst‐free, metal‐free, does not require oxidizing agents. It exhibits wide substrate compatibility can be easily scaled up to gram scale.

Язык: Английский

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A water-soluble type II photosensitizer for selective photooxidation reactions of hydroazaobenzenes, olefins, and hydrosilanes in water

Green Chemistry, Год журнала: 2024, Номер 26(4), С. 2241 - 2247

Опубликована: Янв. 1, 2024

A water-soluble type II photosensitizer with excellent water solubility was utilized for selective photooxidation reactions of hydroazaobenzenes, olefins, and hydrosilanes in water.

Язык: Английский

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Redox Approaches to Carbene Generation in Catalytic Cyclopropanation Reactions

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(29)

Опубликована: Май 16, 2024

Abstract Transition metal‐catalyzed carbene transfer reactions have a century‐old history in organic chemistry and are primary method for the synthesis of cyclopropanes. Much work this field has focused on use diazo compounds related precursors, which can fragment to catalyst with concomitant loss stable byproduct. Despite utility approach, there persistent limitations scope viable carbenes, most notably those lacking stabilizing substituents. By coupling two‐electron redox cycles, it is possible expand available starting materials that be used as precursors. In Minireview, we discuss emerging catalytic reductive cyclopropanation using either gem ‐dihaloalkanes or carbonyl compounds. This strategy inspired by classic stoichiometric transformations, such Simmons–Smith Clemmensen reduction, but instead entails formation catalytically generated transition metal carbenoid. We also present recent efforts generate carbenes directly from methylene (CR 2 H ) groups via formal 1,1‐dehydrogenation. These currently restricted substrates containing electron‐withdrawing substituents, serve facilitate deprotonation subsequent oxidation anion.

Язык: Английский

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Synergistic Brønsted Base/Photoredox‐Catalyzed Three‐Component Coupling with Malonates to Synthesize δ‐Hydroxy Esters and δ‐Keto Esters

Chinese Journal of Chemistry, Год журнала: 2024, Номер 42(9), С. 957 - 962

Опубликована: Янв. 18, 2024

Comprehensive Summary Multicomponent alkene 1,2‐dicarbofunctionalizations (DCFs) have emerged as a powerful strategy to rapidly incorporate both two carbon subunits across one C—C double bond in step for enhancing molecular complexity and diversity. To the best of our knowledge, there is only report on photoredox‐catalyzed three‐component DCFs with malonates through radical−radical cross‐coupling, while radical‐polar crossover (RPC)‐type were still rare. Herein, we describe redox‐neutral RPC‐type 1,2‐dialkylation styrenes aldehydes synergistic Brønsted base/photoredox catalysis system. This transition‐metal‐free provides an efficient clean approach broad variety δ‐hydroxy esters also features exceptionally mild conditions, wide compatibility substrate scope functional groups, high atomic economy. Moreover, 1,2‐alkylacylation from same starting materials was achieved one‐pot manner such coupling subsequent two‐electron oxidation process, providing set δ‐keto interest pharmaceutical research.

Язык: Английский

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Anti-selective Cyclopropanation of Nonconjugated Alkenes with Diverse Pronucleophiles via Directed Nucleopalladation

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(35), С. 24503 - 24514

Опубликована: Авг. 22, 2024

A facile approach to obtaining densely functionalized cyclopropanes is described. The reaction proceeds under mild conditions via the directed nucleopalladation of nonconjugated alkenes with readily available pronucleophiles and gives excellent yields good anti-selectivity using I2 TBHP as oxidants. Pronucleophiles bearing a diverse collection electron-withdrawing groups, including −CN, −CO2R, −COR, −SO2Ph, −CONHR, −NO2, are well tolerated. Internal alkenes, which generally challenging substrates in other cyclopropanation methods, provide diastereoselectivity this methodology, allowing for controlled access substituted at all three C atoms. DFT calculations mechanistic experiments reveal that major pathway involves initial α-iodination nucleophile, followed by anti-carbopalladation intramolecular C(sp3)–I oxidative addition. Strain-release-promoted C(sp3)–C(sp3) reductive elimination then furnishes cyclopropanated product.

Язык: Английский

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Cyano migration-mediated radical-polar crossover cyclopropanation

Science China Chemistry, Год журнала: 2024, Номер unknown

Опубликована: Сен. 3, 2024

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Alkylcyanation of unactivated alkenes via photoinduced hydrogen atom transfer and 1,4-cyano migration

Tetrahedron Letters, Год журнала: 2025, Номер 159, С. 155516 - 155516

Опубликована: Фев. 27, 2025

Язык: Английский

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Oxidative Dicarbofunctionalization of C–C π-Bonds

Elsevier eBooks, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

Язык: Английский

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Late-stage functionalization of pharmaceuticals by C–C cross-coupling enabled by wingtip-flexible N-heterocyclic carbenes

Chem Catalysis, Год журнала: 2025, Номер unknown, С. 101297 - 101297

Опубликована: Фев. 1, 2025

Язык: Английский

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Photochemical Dual Radical Coupling of Carboxylates with Alkenes/Heteroarenes via Diradical Equivalents

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Март 24, 2025

Carboxylate diradical intermediates, with α-carbon and carboxylic oxygen acting as reactive radical centers, represent a highly attractive long-sought species in reaction design synthesis. However, capturing these intermediates for coupling reactions poses formidable challenge due to their inherent instability spontaneous decarboxylation. Here, we addressed this by temporarily masking the carboxylate reactivity via photocleavable dynamic oxygen–iodine bond. This approach effectively prevents unwanted decarboxylation enables controlled utilization of forming new bonds. Carboxylates alkenes/heteroarenes, among most readily available raw materials, can now seamlessly couple pathways form γ-butyrolactones, which are common motifs found numerous natural products bioactive molecules. Ionic traditional carboxylates ruled out based on experimental studies density functional theory (DFT) calculations. strategy overcomes substrate limitations methods, significantly expanding range applicable alkenes/heteroarenes. Our method allows transforming alkenes modes diverse offers insights into developing di- multiradical equivalents unprecedented synthetic designs.

Язык: Английский

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