Transition-Metal-, Additive-, and Solvent-Free [3 + 3] Annulation of RCF₂-Imidoyl Sulfoxonium Ylides with Cyclopropenones to Give Multifunctionalized CF₃-Pyridones

The Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 87(2), P. 1124 - 1132

Published: Dec. 29, 2021

An efficient and practical strategy was developed to synthesize 1,3,4-triaryl-6-trifluoromethylpyridones from CF3-imidoyl sulfoxonium ylides cyclopropenones in good excellent yields. This stepwise [3 + 3] annulation reaction carried out under transition-metal-, additive-, solvent-free conditions, generating 1 equiv of dimethyl sulfoxide as byproduct tolerating a series functional groups.

Language: Английский

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Transition‐Metal‐Free Synthesis of N‐Heterocyclic Compounds via Multi‐Component Reactions

Asian Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 12(9)

Published: July 29, 2023

Abstract Multicomponent reactions (MCRs) have emerged as powerful tools in synthetic chemistry for the efficient synthesis of diverse molecular scaffolds, particularly nitrogen‐containing heterocycles. Despite their numerous advantages, use transition metal catalysts or additives MCRs can present limitations due to cost, toxicity, and environmental concerns. In recent years, there has been a growing interest metal‐free N ‐heterocyclic compounds. This review provides comprehensive concise overview advancements valuable ‐heterocycles over past five years. The is systematically organized, categorizing discussed based on size heterocyclic ring number nitrogen atoms. Only that result formation rings containing at least one atom are included, while derivatization using falls outside scope this review. By highlighting developments field, aims showcase potential significance sustainable strategies accessing elimination metals not only simplifies reaction conditions but also contributes greener more environmentally friendly approaches. serves resource researchers interested design application

Language: Английский

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Evaluation of Pyrones in Bioorthogonal Reactions: Correlation between Structure, Reactivity, and Bioorthogonality

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

Published: Feb. 19, 2025

Alpha-pyrones have been used for applications ranging from total synthesis to antibiotics. However, their application as dienes in bioorthogonal reactions has not extensively explored. In previous work, we demonstrated the promising of ester-functionalized pyrones protein labeling. Here, constructed a library substituted evaluate potential by exploring relationships among structure, reactivity, and bioorthogonality. We found that most pyrone derivatives with electron-withdrawing groups exhibited reactivity toward endo-bicyclo[6.1.0]nonyne (BCN), producing tricyclic tetracyclic products good yields. As expected, more stronger substituents showed faster reaction kinetics BCN. Bicyclic substantially decreased likely resulting increased steric effects. Counterintuitively, substitutions at positions 4 5 affected than those 3 6. To provide insights into both expected counterintuitive reactivities members, performed quantum chemical analysis. Additionally, evaluated each pyrone's L-cysteine no correlation between BCN cysteine-based Finally, collection popular dienophiles reactions.

Language: Английский

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Coumarin-Fused Nitrogenous Heterocycles: An Exploration of Annulation Strategies

Synlett, Journal Year: 2025, Volume and Issue: unknown

Published: March 21, 2025

Abstract Driven by advances in the pharmaceutical industry and materials science, search for innovative strategies synthesis functionalization of coumarin-fused nitrogenous heterocycles has intensified. These compounds, which combine bioactive coumarin core with various nitrogen-containing heterocycles, are significant interest due to their diverse biological activities promising potential applications. Traditional methods synthesizing these hybrid structures often encounter challenges such as low yields, limited functional group compatibility rigorous reaction conditions. To address challenges, there is a growing need development advanced synthetic that can effectively efficaciously produce aforementioned heterocyclic scaffolds. Towards this goal, annulation (e.g., cyclization, condensation, multicomponent reactions, transition-metal-catalyzed etc.) represent pivotal techniques construct evade constraints conventional approaches. In account, we highlight our recent progress on construction complex scaffolds order pave way further developments dynamic field. 1 Introduction 2 Exploring Acid-Catalyzed Annulation Strategies 3 Based C–H Activation 4 Oxidative 5 Conclusion

Language: Английский

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Ru(ii) catalyzed chelation assisted C(sp²)–H bond functionalization along with concomitant (4 + 2) annulation

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(27), P. 5567 - 5586

Published: Jan. 1, 2023

Efficacious protocols have been established to synthesize a structurally privileged Π-extended coumarin-fused pyridone nucleus by activating the vinylic C(sp2)-H bond of coumarin-3-carboxamide under influence inexpensive Ru(II)-metal. Here an N-methoxy carboxamide entity has exploited as chelating fragment manifest functionalization with concomitant (4 + 2) annulation reaction, resulting in heterocyclic ring-forming along sulfoxonium ylide and iodonium representative bench-stable carbene surrogates. This diverse heterocycle formation via insertion strategies, is further expanded activate ortho-C(sp2)-H bonds different heterocycles employing sp2-N moiety directing group develop acyl-alkylated/alkenylated quinazolines, isoxazoles highly fluorescent pyridone-N-oxides. Intriguingly, during evaluation versatility current protocols, one-pot double C-H activation rationalized presence ylide, which results biologically potent benzimidazole-fused coumarin-centered bridge-headed polycyclic heteroarenes. Furthermore, chemo-selective late-stage synthetic transformation being designed differently substituted analogues switching nature reducing agent. In addition, photophysical experiment was done on one pyridine-N-oxide compound (7e) delightfully it exhibited fluorescence quenching activity selectively Al3+ ions, appears be unique feature our methodology. Finally, upon correlation merit developed pathways, mediated strategy superior.

Language: Английский

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Recent trends for chemoselectivity modulation in one-pot organic transformations

RSC Advances, Journal Year: 2024, Volume and Issue: 14(42), P. 31072 - 31116

Published: Jan. 1, 2024

This article describes recent advances in one-pot chemoselective reactions and their mechanism insights. Here, the substrate, catalyst, solvent, temperature play a vital role modulating chemoselectivity.

Language: Английский

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The Construction of Polycyclic Pyridones via Ring-Opening Transformations of 3-hydroxy-3,4-dihydropyrido[2,1-c][1,4]oxazine-1,8-diones

Molecules, Journal Year: 2023, Volume and Issue: 28(3), P. 1285 - 1285

Published: Jan. 28, 2023

This work describes the synthesis of 3-hydroxy-3,4-dihydropyrido[2,1-c][1,4]oxazine-1,8-diones, their tautomerism, and reactivity towards binucleophiles. These molecules are novel convenient building-blocks for direct construction biologically important polycyclic pyridones via an oxazinone ring-opening transformation promoted with ammonium acetate or acetic acid. In case o-phenylenediamine, partial aromatization obtained heterocycles proceeded to form benzimidazole-fused (33-91%).

Language: Английский

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Controllable Synthesis of Two Isomers 4H-Chromene and 2,8-Dioxabicyclo[3.3.1]nonane Derivatives under Catalyst-Free Conditions

The Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 86(23), P. 16396 - 16408

Published: Nov. 16, 2021

A one-pot method for the selective synthesis of two isomers 4H-chromene and 2,8-dioxabicyclo[3.3.1]nonane derivatives was developed without a catalyst using EtOH/H2O (4:1, v/v) as solvent. The reaction conducted under mild conditions, with forming multiple chemical bonds in one pot high atom economy, only stoichiometric amount H2O is produced byproduct. Its selectivity controlled by thermodynamics kinetics, reasons transformation structures are also discussed.

Language: Английский

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Bifunctional Urea/Hg(OAc)₂-Mediated Synthesis of 4-Aryl-6-oxycarbonyl-2-pyrones and 2-Pyridones from Dithiomalonate and β,γ-Unsaturated α-Keto Esters

The Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 86(8), P. 6001 - 6014

Published: April 5, 2021

Disubstituted 2-pyrones and 2-pyridones were obtained by bifunctional urea-catalyzed Michael addition/lactonization or lactamization followed a Hg(OAc)2- Hg(OAc)2/DBU-mediated hydrolysis/decarboxylation/dehydrogenation process. This one-pot two-stage protocol enabled the rapid synthesis of 4,6-disubstituted from dithiomalonate β,γ-unsaturated α-keto esters in practical yields under mild reaction conditions. Additionally, facilely transformed to 2,4,6-trisubstituted pyridines excellent yields.

Language: Английский

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Microwave-assisted DABCO-promoted regioselective [3 + 3] tandem cyclization: synthesis of pyrrolo[3,4-b]pyridine-4-ones from trifluoromethyl-alkynyl esters and α-aminomaleimide

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(29), P. 6039 - 6045

Published: Jan. 1, 2023

A microwave-assisted DABCO-promoted strategy for the regioselective synthesis of pyrrolo[3,4-b]pyridine-4-one derivatives has been developed from [3 + 3] annulation α-aminomaleimide with substituted ethyl 2-butynoate. The characteristic features this methodology include operational simplicity, high regioselectivity, metal-free reaction conditions, and short times. potential utility these methods in biological chemistry medicinal science applications is highlighted.

Language: Английский

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