Metal-Free Aziridination of Unactivated Olefins via Transient N-Pyridinium Iminoiodinanes

JACS Au, Год журнала: 2024, Номер 4(11), С. 4187 - 4193

Опубликована: Окт. 10, 2024

We describe a metal-free aziridination of unactivated olefins to generate

Язык: Английский

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3D honeycomb construction of N-fluorodinitromethyl substituted polynitroazoles based on hydrogen-bonded staggered conformation: Toward high-density melt-cast explosive instead of TNT

Journal of Molecular Structure, Год журнала: 2022, Номер 1264, С. 133337 - 133337

Опубликована: Май 18, 2022

Язык: Английский

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Benzylic C(sp³)−H Alkoxylation through Visible‐Light‐Driven Oxidative Radical‐Polar Crossover

Asian Journal of Organic Chemistry, Год журнала: 2024, Номер 13(4)

Опубликована: Фев. 8, 2024

Abstract We report a metal‐free method for benzylic C(sp 3 )−H alkoxylation with silyl ether as an alkoxylating agent. The reaction is considered to proceed through sequence consisting of hydrogen atom transfer (HAT) and oxidative radical‐polar crossover, wherein Selectfluor serves one‐electron oxidant, HAT agent, fluoride ion source. formed in situ activates the give alkoxide nucleophile, which reacts benzyl cation intermediate provide product. present protocol has broad substrate scope, enabling C−H primary, secondary, tertiary bonds. Furthermore, it applicable late‐stage bioactive molecules.

Язык: Английский

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Redox-neutral α-functionalization of pyrrolidines: facile access to α-aryl-substituted pyrrolidines

RSC Advances, Год журнала: 2024, Номер 14(17), С. 11986 - 11991

Опубликована: Янв. 1, 2024

α-Aryl-substituted pyrrolidine moiety is found in many natural alkaloids. Starting from pyrrolidine, we were able to synthesize α-aryl-substituted pyrrolidines one step using quinone monoacetal as the oxidizing agent and DABCO base. We also discovered reaction condition needed efficiently remove N-aryl α-arylated product. When above was carried out without addition of an aryl nucleophile, 2,2,2-trifluoroethanol afforded octahydro-dipyrroloquinoline high yield, which has same skeleton that product incargranine B.

Язык: Английский

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Studies on the Biomimetic Synthesis of Marine Ladder Polyethers via Endo‐Selective Epoxide‐to‐Epoxonium Ring‐Opening Cascades

Angewandte Chemie, Год журнала: 2024, Номер 136(30)

Опубликована: Май 16, 2024

Abstract Marine ladder polyethers have attracted the attention of chemists and biologists because their potent biological activities. Synthetic attempted to construct polyether frameworks by epoxide ring‐opening cascades, as Nakanishi hypothesis describes. However, Baldwin's rules ring closure state that exo ‐selective intramolecular cyclization epoxy alcohols is preferred over endo cyclization. Herein, we investigated cascades polyepoxy in [EMIM]BF 4 /PFTB (1‐ethyl‐3‐methylimidazolium tetrafluoroborate /perfluoro‐ tert ‐butyl alcohol) found all‐ products were formed via epoxide‐to‐epoxonium cyclizations (not restricted rules, which only apply hydroxyl‐to‐epoxide cyclizations). We determined key factor enabling undergo a high proportion was inhibition starting from terminal hydroxyl group alcohol. By introducing slow‐release protecting group, could markedly increase yields fragments with hydrogen atoms at junctions. For first time, constructed consecutively fused six‐membered‐ring seven‐, eight‐, nine‐membered‐ring through addition suitable Lewis acid. also suggest biosynthesis marine may proceed polyepoxide.

Язык: Английский

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Solvent-dependent chemoselective synthesis of different isoquinolinones mediated by the hypervalent iodine(III) reagent PISA

Beilstein Journal of Organic Chemistry, Год журнала: 2024, Номер 20, С. 1914 - 1921

Опубликована: Авг. 7, 2024

Isoquinolinone is an important heterocyclic framework in natural products and biologically active molecules, the efficient synthesis of this structural motif has received much attention recent years. Herein, we report a (phenyliodonio)sulfamate (PISA)-mediated, solvent-dependent different isoquinolinone derivatives. The method provides highly chemoselective access to 3- or 4-substituted derivatives by reacting

Язык: Английский

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Mechanistic Insights into Copper-Mediated Benzylic C(sp³)−H Bond Trifluoromethylation

Organic & Biomolecular Chemistry, Год журнала: 2024, Номер unknown

Опубликована: Янв. 1, 2024

The trifluoromethylation of primary and secondary benzylic C(sp 3 )−H bonds by Cu II species proceeds via a radical recombination/reductive elimination pathway, while tertiary prefer the single-electron transfer (SET) pathway.

Язык: Английский

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Electrooxidative Pd-Catalyzed Remote Hydrofunctionalization of Alkenes with Nucleophiles

ACS Catalysis, Год журнала: 2024, Номер 14(21), С. 15858 - 15868

Опубликована: Окт. 11, 2024

The catalytic hydrofunctionalization of alkenes with nucleophiles via the generation carbocationic intermediates has been extensively studied as an efficient strategy for regioselective installation functional groups on alkene feedstocks. However, since established methods are confined to functionalization position where is originally located, it highly desirable develop a broadly applicable platform that offers alternative regioselectivity otherwise challenging achieve existing protocols. Herein, we report remote method enabled by electrooxidative palladium hydride catalysis. key success formation carbocation intermediate through mechanistic pathway, which involves chain-walking process followed anodic oxidation organopalladium species. This allows terminal and internal broad range oxygen, carbon, nitrogen, fluoride nucleophiles, including complex drug-like molecules.

Язык: Английский

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Unraveling Alcohol Additive Effects on Hypervalent Iodine(III)-Catalyzed Asymmetric Phenolic Dearomatization: Ligand Substitution and Low-Barrier Hydrogen Bonds

ACS Catalysis, Год журнала: 2024, Номер 15(1), С. 370 - 380

Опубликована: Дек. 18, 2024

Despite the widespread use of hexafluoropropanol (HFIP) as a "magic" solvent or additive in organic synthesis, its fundamental mechanisms lag far behind. This study presents mechanistic insights into puzzling alcohol effects observed Ishihara's conformationally flexible C2-symmetric iodoarene-catalyzed asymmetric phenolic dearomatization through density functional theory calculations. The results reveal that due to "booster effect" fluorinated alcohols, HFIP assembles trimeric hydrogen bond cluster displaces ligand from active iodine(III) catalyst and forms low-barrier with substrate, which significantly enhances oxidizing power center, thus facilitating electron-deficient phenols. Conversely, methanol is found promote electron-rich phenols via formally similar yet distinct mechanism, highlighting unique role an additive. gained this investigation advance our molecular-level understanding synergistic interactions between catalysts additives, potentially guiding design catalytic systems exploit these for broader applications.

Язык: Английский

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Elucidating solvent effects on the stability of phenoxyl radicals in monohydric alcohols via electron paramagnetic resonance

Green Chemical Engineering, Год журнала: 2023, Номер 5(4), С. 483 - 488

Опубликована: Дек. 26, 2023

Research on solvent effects is an important and long-standing topic, but there still some room, especially for the special effect of fluoroalcohols. In this work, we investigated stability phenoxyl radical in monohydric alcohol solvents through in-situ electron paramagnetic resonance detections. The decay behavior showed a reasonable relationship with mesoscopic structure alcohols, characterized by small- wide-angle X-ray scattering. Moreover, distinct fluoroalcohols were emphasized, significant influence van der Waals distance was suggested. Overall, alcohols quantified correlated structures. We believe that established method study radicals will encourage studies various organic reactions, proposed may inspire development green both industrial conversions synthesis.

Язык: Английский

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