Divergent Synthesis of Four Types of Fused N‐Containing Heterocycles via Oxidative Multi‐Component Cyclization Reaction

Chinese Journal of Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 31, 2025

Comprehensive Summary An atmospheric‐oxygen‐mediated four‐component reaction was developed for the divergent synthesis of pyrazolo[1,5‐ a ]pyrimidine and pyrazolo[3,4‐ b ]pyridine derivatives from readily available alcohols 3‐aminopyrazoles. In this transformation, atmospheric oxygen serves as green oxidant, promoting equivalent aldehydes four types N ‐containing heterocycles (> 40 examples). Remarkably, transformation features metal‐free molecular diversity.

Language: Английский

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Oxygen Migration–Defluorination Strategy Enables the Aminocarbonylation of Enaminones with o-Aminobenzamides and CF₂Br₂

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 24, 2025

The development of different concept approaches and user-friendly carbonyl surrogates for aminocarbonylation is highly desirable. Herein, we report the photocatalytic enaminones with easily available o-aminobenzamides CF2Br2 through an oxygen migration-defluorination strategy. reaction features switchable transformation construction carbamoyl-substituted enol products allows expedient synthesis fully substituted maleimides under mild conditions.

Language: Английский

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Facile synthesis of the unknown 6,7-dihydrofuro[3,4-c]pyridines and 3,4-diaryloylpyridines from N-propargyl β-enaminones

Organic & Biomolecular Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

A simple methodology for the synthesis of bicyclic 6,7-dihydrofuro[3,4- c ]pyridines is reported. The skeletal diversity synthesized heterobicyclic frame may present new nitrogen- and oxygen-based hybrid systems medicinal chemistry.

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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NBS-Mediated C(sp2)-H Bond Chlorination of Enaminones: Using DCE as Chlorine Source

International Journal of Molecular Sciences, Journal Year: 2024, Volume and Issue: 25(22), P. 12073 - 12073

Published: Nov. 10, 2024

Commercial DCE is excavated as both a "Cl" source and solvent for the vinyl C(sp

Language: Английский

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Molecular-Oxygen-Mediated Multicomponent Oxidative Cyclization: Synthesis of Tertiary-Alcohol-Unit-Bearing N-Heterocycles via Transforming C–H to C–OH Bonds

Organic Letters, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 26, 2024

We developed a molecular-oxygen-mediated multicomponent oxidative cyclization strategy to synthesize N-heterocycles containing tertiary alcohol units via the formation of key C–OH bonds and quaternary carbon centers. This formal [3 + 2 1] annulation offers green sustainable alternative for de novo bond formation, using O2 as both oxidant oxygen source under metal- catalyst-free conditions. Notably, continuous [1,5]-hydrogen transfer together with excess alcohols promotes C–OH-bearing products. Additionally, generation centers inhibits conversion C═O bonds, thus stabilizing desired

Language: Английский

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