The Electrochemical Iodination of Electron‐Deficient Arenes

Angewandte Chemie International Edition, Год журнала: 2025, Номер unknown

Опубликована: Янв. 28, 2025

Abstract The iodination of electron‐deficient arenes and heteroarenes is a long‐standing problem in organic synthesis. Herein we describe the electrochemical nitromethane with Bu 4 NI as iodine source supporting electrolyte under Lewis acid‐free conditions presence small amounts chloride anions. electrochemically generated reagent could be applied for halogenated arenes, aromatic aldehydes, acids, esters, ketones, well nitroarenes to afford products good excellent yields.

Язык: Английский

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Regioselective synthesis of 4-functionalized pyridines

Chem, Год журнала: 2023, Номер 10(2), С. 628 - 643

Опубликована: Ноя. 21, 2023

Язык: Английский

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Late-Stage Halogenation of Complex Substrates with Readily Available Halogenating Reagents

Accounts of Chemical Research, Год журнала: 2024, Номер 57(21), С. 3161 - 3181

Опубликована: Сен. 20, 2024

ConspectusLate-stage halogenation, targeting specific positions in complex substrates, has gained significant attention due to its potential for diversifying and functionalizing molecules such as natural products pharmaceutical intermediates. Utilizing readily available halogenating reagents, hydrogen halides (HX), N-halosuccinimides (NXS), dichloroethane (DCE) reagents late-stage halogenation shows great promise expanding the toolbox of synthetic chemists. However, reactivity haleniums (X

Язык: Английский

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Formal meta-C–H-Fluorination of Pyridines and Isoquinolines through Dearomatized Oxazinopyridine Intermediates

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(45), С. 30758 - 30763

Опубликована: Ноя. 1, 2024

Organofluorine compounds, including fluorinated pyridines and isoquinolines, play a crucial role in pharmaceuticals, agrochemicals, materials science. However, step-economic selective C-H-functionalization to access these azaarenes is still underexplored, with

Язык: Английский

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C—F Bond Insertion into Indoles with CHBr₂F: An Efficient Method to Synthesize Fluorinated Quinolines and Quinolones

Chinese Journal of Chemistry, Год журнала: 2024, Номер 42(10), С. 1128 - 1132

Опубликована: Фев. 6, 2024

Comprehensive Summary A mild and practical method for synthesizing fluorinated quinoline derivatives, which have a wide range of applications in pharmaceuticals, materials, organic synthesis, was described through C—F bond insertion into indoles using CHBr 2 F. The simple conditions, readily availability F, as well the versatility transformations make this strategy very powerful 3‐fluoroquinoline 3‐fluoroquinolone. mechanistic studies reveal that bromofluorocarbene generated in‐situ under basic condition key intermediate.

Язык: Английский

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C3 Selective chalcogenation and fluorination of pyridine using classic Zincke imine intermediates

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Авг. 28, 2024

Regioselective C-H functionalization of pyridines remains a persistent challenge due to their inherent electronically deficient properties. In this report, we present strategy for the selective pyridine C3-H thiolation, selenylation, and fluorination under mild conditions via classic N-2,4-dinitrophenyl Zincke imine intermediates. Radical inhibition trapping experiments, as well DFT theoretical calculations, indicated that thiolation selenylation proceeds through radical addition-elimination pathway, whereas two-electron electrophilic substitution pathway. The pre-installed electron-deficient activating N-DNP group plays crucial positive role, with additional benefit recyclability. practicability protocol was demonstrated in gram-scale synthesis late-stage modification pharmaceutically relevant pyridines.

Язык: Английский

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Advances in Pyridine C – H Functionalizations: Beyond C2 Selectivity

Chemistry - A European Journal, Год журнала: 2024, Номер 31(2)

Опубликована: Ноя. 28, 2024

The pyridine core is a crucial component in numerous FDA-approved drugs and Environmental Protection Agency (EPA) regulated agrochemicals. It also plays significant role ligands for transition metals, alkaloids, catalysts, various organic materials with diverse properties, making it one of the most important structural frameworks. However, despite its significance, direct selective functionalization still relatively underdeveloped due to electron-deficient nature strong coordinating ability nitrogen. Among variety synthetic transformation, C-H bond straightforward atom economical approach it's advantageous late-stage containing drugs. In recent years, innovative strategies regioselective pyridines azines have emerged, offering benefits such as high regioselectivity, mild conditions, enabling transformations that were challenging traditional methods. This review emphasizes latest advancements meta para-C-H through approaches, including phosphonium salts, photocatalytic methods, temporary de-aromatization, Minisci-type reactions, metal-catalyzed activation techniques. We discuss advantages limitations these current methods aim inspire further progress this field.

Язык: Английский

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Die Elektrochemische Iodierung von Elektronenarmen Aromaten

Angewandte Chemie, Год журнала: 2025, Номер unknown

Опубликована: Янв. 28, 2025

Abstract Die direkte Iodierung von elektronenarmen Aromaten und Heteroaromaten ist ein seit langer Zeit ungelöstes Problem in der Organischen Synthese. In diesem Beitrag beschreiben wir die elektrochemische Nitromethan mit Bu 4 NI als Iodid‐Quelle Leitsalz unter Lewis‐Säure freien Bedingungen Anwesenheit katalytischen Mengen Chlorid‐Ionen. Das elektrochemisch generierte Reagenz konnte für halogenierten Aromaten, aromatischen Aldehyden, Säuren, Estern, Ketonen sowie Nitroaromaten genutzt werden, um gewünschten Produkte guten bis exzellenten Ausbeuten zu erzeugen.

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N-Boryl Pyridyl Anion Chemistry

Accounts of Chemical Research, Год журнала: 2025, Номер unknown

Опубликована: Фев. 27, 2025

ConspectusPyridine is a crucial heterocyclic compound in organic chemistry. Typically, the pyridine motif behaves as an N-nucleophile and electron-deficient aromatic ring. Transforming ring into electron-rich system that exhibits reactivity contrary to classical expectations could unveil new opportunities This Account describes approach umpolung of through formation unprecedented N-boryl pyridyl anion (N-BPA) intermediate enables catalysis transformations.In 2017, we discovered 4-phenylpyridine acts efficient catalyst for borylation iodo- bromoarenes using diboron(4) compounds. Mechanistic studies revealed situ N-BPA pyridine/diboron(4)/methoxide reaction pivotal step this transformation. Further investigations showed dual reactivities both strong electron donor potent nucleophile. unique profile has unveiled novel pathways redox catalysis, derivatizations, transformations.Based on electron-donor characteristic anion, have developed catalytic mediated by catalyst. In pyridine/diboron(4)/base system, followed single transfer (SET) substrate with regeneration molecule establishes cycle. single-electron reduction variety substrates employing source. Upon visible-light excitation, transitions its excited state, exhibiting significantly enhanced reductivity. establishment modular photoredox consisting various combinations allow fine-tuning property. Using strategy, performed series challenging reactions, including -electron nonactivated chloro- fluoroarenes, Birch arenes.The nucleophilic character was effectively harnessed facilitate derivatization transformations. By directly quenching situ-generated proton source, practical N-H-1,4-dihydropyridines (DHPs). Bimolecular substitution between alkyl bromide produced 4-alkyl-1,4-DHP, which subsequently releases radical under conditions. process enabled transformation bromides radicals. Employing 4-trifluoromethylpyridine chemistry, resulting undergoes elimination fluoride yield 4-pyridyldifluoromethyl nucleophile, then reacts electrophiles realize defluorinative functionalization forge pyridyldifluoromethyl Alternatively, when 4-perfluoroalkylthiopyridine employed, similar occurred form perfluoroalkyl demonstrating perfluoroalkylation reagent offers distinct advantages over traditional reagents.The described provide insights We anticipate these findings will inspire further exploration mechanisms related

Язык: Английский

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Visible Light-Promoted Defluorinative Alkylation of Trifluoromethyl Ketones with α-Aminoalkyl Boron Species

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Апрель 14, 2025

In this study, we developed a photoredox-catalyzed defluorinative cross-coupling method for trifluoroketones and alkyl boronic acids. The reaction afforded series of novel α,α-difluoroketone derivatives, in vitro fungicidal activity revealed that some these compounds exhibited moderate to excellent against Rhizoctonia solani Botrytis cinerea. particular, compound 3d showed an EC50 value 4.27 μg/mL B. cinerea can be used as lead further optimization.

Язык: Английский

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