Recent advances in iodine–DMSO mediated C(sp³)–H functionalization of methyl-azaarenes via Kornblum oxidation

New Journal of Chemistry, Journal Year: 2024, Volume and Issue: 48(17), P. 7614 - 7638

Published: Jan. 1, 2024

In the iodine–DMSO medium, methyl group of azaarenes is converted into aldehyde via Kornblum oxidation and trapped in situ by nucleophiles to create azaarene-linked functionalized scaffolds.

Language: Английский

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Citric Acid-Catalyzed Three-Component Synthesis of (E)-3-Aryl-2-styryl-2,3-dihydroquinazoline-4(1H)-ones and Their Mild Oxidation with I2/DMSO System into (E)-3-Aryl-2-styrylquinazolin-4(3H)-ones

Chemistry, Journal Year: 2025, Volume and Issue: 7(2), P. 42 - 42

Published: March 16, 2025

We hereby report a simple and efficient method for the preparation of (E)-3-aryl-2-styryl-2,3-dihydroquinazolin-4-(1H)-ones, from isatoic anhydride, anilines, cinnamaldehydes in presence 20 mol% citric acid methanol at 60 °C 2 h. The styryl-dihydroquinazolin-4-(1H)-one products were obtained moderate good yields (30–80%) through three-component condensation reaction, under an environment-friendly protocol. latter easily transformed into styrylquinazolin-4-(3H)-one derivatives with 57–91% using mild oxidation I2/DMSO system less than min.

Language: Английский

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I₂-Catalyzed Cascade Annulation/Cross-Dehydrogenative Coupling: Excellent Platform to Access 3-Sulfenyl Pyrazolo[1,5-a]pyrimidines with Potent Antibacterial Activity against Pseudomonas aeruginosa and Staphylococcus aureus

ACS Applied Bio Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 19, 2025

The increasing resistance of bacteria to antibiotics has become a serious threat existing options for treating bacterial infections. We have developed synthetic methodology 3-sulfenyl pyrazolo[1,5-a]pyrimidines with potent antibacterial activity. This iodine-catalyzed strategy been by employing amino pyrazoles, enaminones/chalcones, and thiophenols through intermolecular cyclization subsequent cross-dehydrogenative sulfenylation. highly regioselective practicable protocol utilized synthesize structurally diverse wide functionalities. is also extendable toward the synthesis bis(pyrazolo[1,5-a]pyrimidin-3-yl)sulfanes from pyrazole, enaminones/chalcone, KSCN pyrazolo[1,5-a]pyrimidine direct acetophenone. Mechanistic investigation disclosed radical pathway C-H sulfenylation involvement 3-iodo as active intermediate. biological activity sulfenyl against Pseudomonas aeruginosa Staphylococcus aureus, whereas sulfinyl no such Sulfenyl mechanistically inhibited growth accumulation ROS well induction in lipid peroxidation. Subsequently, circumstances changed membrane potential facilitated interaction membrane-associated proteins, leading loss integrity damage cell membranes. Moreover, these derivatives potentiated efficacy commercial antibiotic ciprofloxacin selected strains can be considered an alternative therapy

Language: Английский

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TCT-Mediated and Water-Controlled Synthesis of Benzofuran-3(2H)-ones Bearing a Quaternary Carbon Center via a Radical Process Using Dimethyl Sulfoxide as a Dual Synthon

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

Published: April 10, 2025

An efficient and attractive method for the synthesis of valuable benzofuran-3(2H)-one derivatives bearing a quaternary center in one step by employing dimethyl sulfoxide (DMSO) as dual synthon under metal-free conditions has been developed. In this reaction, DMSO activated cyanuric chloride (TCT) provides two different units (CH3 SMe) target molecules, construction carbon benzofuran-3(2H)-ones can be controlled addition water. Furthermore, functional group compatibility synthetic value were demonstrated scope evaluation gram-scale experiments. The mechanistic studies show that reaction may proceed via radical process.

Language: Английский

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Straightforward Access to 4-Sulfenylated Isocoumarins via Sulfoxides/MOMCl-Enabled Regioselective Cleavage and Reconfiguration of C–S Bonds

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

Published: April 22, 2025

The combination of sulfoxides with MOMCl has been found for the first time to mediate electrophilic cyclization and install a variety sulfenyl groups onto isocoumarin skeletons via regioselective cleavage reconfiguration C-S bonds. Notably, MOMCl, mild readily available alkyl chloride, was indispensable played significant role as an activator under neutral conditions in this transformation, thus expanding scope acid-labile substrates.

Language: Английский

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Iodine-Catalyzed Room-Temperature Aerobic Oxidation of C(sp³)–H Bonds and Its Application in the Synthesis of Quinoxaline Derivatives

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

Published: May 1, 2025

An iodine-catalyzed aerobic oxidation reaction of C(sp3)-H bonds was established at room temperature. In this transformation, iodine acts as a Lewis acid catalyst, and the pyridine moiety in substrate plays crucial role. Under optimum conditions, picolyl ketone substrates were smoothly transformed into corresponding 1,2-dicarbonyl compounds, subsequent introduction 1,2-diaminobenzenes mixture led to formation various quinoxaline derivatives. This synthetic process does not use transition metals also features mild operational simplicity, gram-scale synthesis.

Language: Английский

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A Transition Metal‐Free Strategy for Dihydrobenzazepinoindole via KI‐Mediated Oxidative Pictet–Spengler Reaction

Chemistry - An Asian Journal, Journal Year: 2025, Volume and Issue: unknown

Published: May 1, 2025

A transition-metal-free synthesis of dihydrobenzazepinoindoles has been developed using a potassium iodide (KI)-mediated oxidative Pictet-Spengler reaction under mild conditions. While the classical cyclization is well-established, its variant remains underexplored. This method offers sustainable and efficient approach, providing operational simplicity, broad substrate scope, enhanced environmental compatibility. The tolerates various functional groups, enabling access to structurally diverse dihydrobenzazepinoindole derivatives. synthesized compounds were fully characterized 1H NMR, 13C DEPT-135, IR, mass spectrometry, confirming their structural integrity. scalability this demonstrated through successful large-scale synthesis. plausible mechanism proposed, shedding light on role KI in cyclization. study underscores potential as an environmentally benign promoter presents practical alternative traditional metal-mediated methodologies for nitrogen-containing heterocycles.

Language: Английский

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Transforming an azaarene into the spine of fusedbicyclics via cycloaddition-induced scaffold hopping of 5-Hydroxypyrazoles

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Dec. 30, 2024

Skeleton editing for heteroarenes, especially pyrazoles, is challenging and remains scarce because these non-strained aromatics exhibit inert reactivities, making them relatively inactive performing a dearomatization/cleavage sequence. Here, we disclose cycloaddition-induced scaffold hopping of 5-hydroxypyrazoles to access the pyrazolopyridopyridazin-6-one skeleton through single-operation protocol. By converting five-membered aza-arene into five-unit spine 6/6 fused-bicyclic, this work unlocks ring-opening reactivity pyrazole core that involves formal C = N bond cleavage while retaining highly reactive N-N in resulting product. A [4 + 2] cycloaddition temporarily dearomatized 5-hydroxypyrrole with an situ generated aza-1,3-diene, followed by oxidative C-N cleavage, constitutes domino pathway. library pyrazolopyridopyridazin-6-ones, which are medicinally relevant nitrogen-atom-rich tricyclics, obtained efficiently from readily available materials.

Language: Английский

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From an Azaarene to the Spine of Fused Bicyclics: Cycloaddition-Induced Scaffold Hopping of 5-Hydroxypyrazoles

Research Square (Research Square), Journal Year: 2024, Volume and Issue: unknown

Published: July 9, 2024

Skeleton editing for heteroarenes, especially pyrazoles, is challenging and remains scarce due to these non-strained aromatics feature inert reactivities therefore relatively inactive perform a dearomatization/cleavage sequence. Herein, we disclose cycloaddition-induced scaffold hopping of 5-hydroxypyrazoles access pyrazolopyridopyridazin-6-one skeleton in single-operation protocol. By converting five-membered azaarene into five-unit spine 6/6 fused-bicyclics, this work has unlocked new ring-opening reactivity pyrrole core that involves formal C = N bond cleavage while retaining the highly reactive N-N resulting product. A [4 + 2] cycloaddition temporary dearomatized 5-hydroxypyrrole with anin situgenerated aza-1,3-diene follow-up oxidative C-N accounted domino pathway. library pyrazolopyridopyridazin-6-one, which are medicinally relevant nitrogen-atom-rich tricyclics, was obtained efficiently from readily available materials.

Language: Английский

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Three‐Component Synthesis of Fluorescent 1,4‐Benzothiazin‐2‐ones through Thiol‐Free Iodine‐Catalyzed Cyclization

European Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 27(42)

Published: Aug. 9, 2024

Abstract A convergent synthesis of 2 H ‐benzo[ b ][1,4]thiazin‐2‐one was achieved via iodine‐catalyzed three‐component reaction. This strategy involves the formation two new C−S bonds and a C−N bond from readily available precursors ‐ aryl methyl ketones, p ‐anisidine, elemental sulfur to generate desired heterocycle in moderate good yields. As synthesized benzothiazine‐2‐ones are fluorescent under UV light, photophysical properties like solid‐state emission, solvatochromism, Aggregation Induced Emission (AIE), relative quantum yields compounds were measured which proves them be potential candidate for development optoelectronic devices.

Language: Английский

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