Pd-Catalyzed Strain-Releasing Dyotropic Rearrangement: Ring-Expanding Amidofluorination of Methylenecyclobutanes

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

Опубликована: Март 2, 2025

Under the Pd(II)/Pd(IV) catalytic cycle, cyclization of pent-4-en-1-amine derivatives typically yields either pyrrolidines or piperidines depending on N-protecting group. We report herein an unprecedented Pd(II)-catalyzed oxidative domino process that converts readily accessible N-protected 2-(2-amidoethyl)-1-methylenecyclobutane to 1-fluoro-2-azabicyclo[3.2.1]octanes. This transformation constructs three chemical bonds under mild conditions [Pd(hfacac)2 (5.0 mol %), Selectfluor (2.0 equiv), MeCN, 60 °C, 10 min] through a sequence involving 5-exo-trig amidopalladation/Pd(II)–oxidation/chemoselective dyotropic rearrangement/C–F bond-forming reductive elimination. Notably, mode remains independent group these conditions. Furthermore, diverse functional groups can be introduced at bridgehead position bicyclic compound via apparent anti-Bredt iminium intermediate.

Язык: Английский

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Recent Advancement on Selectfluor Mediated Synthesis of Heterocyclic Molecules

The Chemical Record, Год журнала: 2025, Номер unknown

Опубликована: Янв. 16, 2025

Abstract Selectfluor, [1‐chloromethyl‐4‐fluoro‐1,4‐diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate)], is a highly valuable reagent in contemporary chemistry, serving not only as an electrophilic fluorinating agent but also effective catalyst the synthesis of various pharmaceutically relevant heterocycles. This review article seeks to present comprehensive overview significant heterocyclic ring formations facilitated by selectfluor. Both metal‐free and metal‐catalyzed recent advancement on selectfluor mediated cyclisation processes are discussed this mainly over last eight years (2017‐April 2024).

Язык: Английский

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Editing Tetrasubstituted Carbon: Dual C–O Bond Functionalization of Tertiary Alcohols Enabled by Palladium-Based Dyotropic Rearrangement

Journal of the American Chemical Society, Год журнала: 2024, Номер unknown

Опубликована: Апрель 8, 2024

Many elegant asymmetric syntheses of enantioenriched tertiary alcohols have been developed, and both the transition metal-catalyzed radical-based peripheral functionalization attracted intensive research interest in recent years. However, directly editing tetrasubstituted carbons remains challenging. Herein, we report a Pd-catalyzed migratory fluoroarylation reaction that converts to α-fluorinated alkyl ethers good excellent yields. An unprecedented 1,2-aryl/PdIV dyotropic rearrangement along C–O bond, integrated PdII-catalyzed domino process, is key dual hydroxyl group carbon. This reaction, which compatible with broad range functional groups, generates fluoride an alkyl-aryl ether inversion absolute configuration at stereocenter.

Язык: Английский

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Palladium‐Based Dyotropic Rearrangement Enables A Triple Functionalization of Gem‐Disubstituted Alkenes: An Unusual Fluorolactonization Reaction

Angewandte Chemie International Edition, Год журнала: 2023, Номер 63(1)

Опубликована: Ноя. 21, 2023

We report in this paper a Pd(II)-catalyzed migratory gem-fluorolactonization of ene-carboxylic acids. Reaction 4-methylenealkanoic acid derivatives with Selectfluor the presence Pd(OAc)2 (1.0 mol %) at room temperature affords fluorolactones good to excellent yields. 2-(2-Methylenecycloalkanyl)acetic acids are transformed bridged under identical conditions. One C-C, one C-O and tertiary C-F bond were generated along gem-disubstituted carbon-carbon double operationally simple transformation. Trapping experiments indicates that reaction is initiated by 5-exo-trig oxypalladation followed Pd oxidation, regioselective ring-enlarging 1,2-alkyl/Pd(IV) dyotropic rearrangement forming reductive elimination cascade. Post-transformations these taking advantage electrophilicity 1-fluoroalkylcarboxylate function also documented.

Язык: Английский

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Quaternary Carbon Editing Enabled by Sequential Palladium Migration

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(31), С. 21239 - 21244

Опубликована: Июль 25, 2024

Peripheral functionalization of a quaternary carbon via C(sp3)–H bond activation has made significant progress in recent years. However, direct editing through Csp3–Csp3 cleavage and refunctionalization nonstrained acyclic molecules remain underexploited. Herein we report reaction which methyl group attached to is shifted its neighboring secondary with concurrent oxidation the C–C single C═C double bond. Specifically, morpholinyl amide 2,2-dimethyl alkanoic acids converted 2-methylene-3-methyl acid derivatives presence catalytic amount palladium acetate, Selectfluor sodium carbonate. Control experiments suggest that proceeds sequence selective group, resulting C(sp3)–PdII PdIV intermediate followed by unprecedented 1,3-PdIV migration, 1,2-methyl/PdIV dyotropic rearrangement finally, β–Hydride elimination. In this domino process, migrates successively from primary finally carbon, leading primary, secondary, carbon.

Язык: Английский

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Nickel-catalyzed ligand-controlled switchable skeletal rearrangements: divergent synthesis of isoquinoline-1,3-diones, cyclohexenols, cycloheptenols, and 2-benzazepin-5-ones

Science China Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Фев. 6, 2025

Язык: Английский

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Enantioselective [5 + 1] cycloaddition of sulfur ylides and vinylethylene carbonates via synergistic palladium/chiral phosphonic acid catalysis

Chemical Science, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

An effective method for the synthesis of dihydropyrans through synergistic palladium and chiral phosphonic acid catalysis was reported. This protocol proceeded under mild reactions provided in up to 87% yield 97% ee.

Язык: Английский

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Nitrogen-Based Organofluorine Functional Molecules: Synthesis and Applications

Chemical Reviews, Год журнала: 2025, Номер unknown

Опубликована: Апрель 22, 2025

Fluorine and nitrogen form a successful partnership in organic synthesis, medicinal chemistry, material sciences. Although fluorine-nitrogen chemistry has long rich history, this field received increasing interest made remarkable progress over the past two decades, driven by recent advancements transition metal organocatalysis photochemistry. This review, emphasizing contributions from 2015 to 2023, aims update state of art synthesis applications nitrogen-based organofluorine functional molecules chemistry. In dedicated sections, we first focus on fluorine-containing reagents organized according type groups attached nitrogen, including N-F, N-RF, N-SRF, N-ORF. review also covers nitrogen-linked building blocks, catalysts, pharmaceuticals, agrochemicals, underlining these components' broad applicability growing importance modern

Язык: Английский

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An Aza‐Prilezhaev‐Based Method Inverts Regioselectivity in Stereospecific Alkene 1,2‐Aminohydroxylations

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(49)

Опубликована: Авг. 22, 2024

Abstract Under acidic conditions (TFA) and in the presence of water, BocNHOTs promotes stereospecific 1,2‐aminohydroxylations alkenes. The processes involve intermolecular aza‐Prilezhaev aziridination followed by S N 2 opening water. This reagent combination provides regiochemical outcomes that are opposite to, or more selective than those observed using epoxidation initiated 1,2‐aminohydroxylation protocols. Replacement water other nucleophiles allows 1,2‐amino(thio)etherification, diamination, aminoazidation aminofluorination reactions. Intramolecular also feasible, including unusual variants evoke azabicyclobutane‐like reactivity.

Язык: Английский

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Palladium/Xu-Phos-catalyzed enantioselective arylalkoxylation reaction of γ-hydroxyalkenes at room temperature

Chinese Chemical Letters, Год журнала: 2024, Номер 35(11), С. 109879 - 109879

Опубликована: Апрель 10, 2024

Язык: Английский

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