Aroyl Fluorides as Bifunctional Reagents for Dearomatizing Fluoroaroylation of Benzofurans

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(16), P. 7072 - 7079

Published: March 22, 2022

The 2,3-dihydrobenzofuran scaffold is widely found in natural products and biologically active compounds. Herein, dearomatizing 2,3-fluoroaroylation of benzofurans with aroyl fluorides as bifunctional reagents to access 2,3-difunctionalized dihydrobenzofurans reported. reaction that occurs by cooperative NHC/photoredox catalysis provides 3-aroyl-2-fluoro-2,3-dihydrobenzofurans moderate good yield high diastereoselectivity. Cascades proceed via radical/radical cross-coupling a benzofuran radical cation generated the photoredox cycle neutral ketyl formed through NHC cycle. redox-neutral transformation exhibits broad substrate scope functional group compatibility. With anhydrides reagents, aroyloxyacylation achieved strategy can also be applied

Language: Английский

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Electrochemical Dearomative Spirocyclization

Chemistry - An Asian Journal, Journal Year: 2023, Volume and Issue: 18(9)

Published: March 15, 2023

Electrochemical dearomative spirocyclization serves as a green and sustainable approach to convert the flat, two-dimension aromatic feedstock into value-added three-dimension spirocyclic architectures. This review highlights recent advances, emphasizes mechanistic discussions, showcases synthetic applications of this emerging versatile powerful transformation.

Language: Английский

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Formation of Isolable Dearomatized [4 + 2] Cycloadducts from Benzenes, Naphthalenes, and N-Heterocycles Using 1,2-Dihydro-1,2,4,5-tetrazine-3,6-diones as Arenophiles under Visible Light Irradiation

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(16), P. 9326 - 9333

Published: April 13, 2023

We report that the dearomative [4 + 2] cycloaddition between 1,2-dihydro-1,2,4,5-tetrazine-3,6-diones (TETRADs) and benzenes, naphthalenes, or N-heteroaromatic compounds under visible light irradiation affords corresponding isolable cycloadducts. Several synthetic transformations including transition-metal-catalyzed allylic substitution reactions using isolated cycloadducts at room temperature above were demonstrated. Computational studies revealed retro-cycloaddition of benzene–TETRAD adduct proceeds via an asynchronous concerted mechanism, while benzene–MTAD (MTAD = 4-methyl-1,2,4-triazoline-3,5-dione) a synchronous mechanism.

Language: Английский

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Transfer Hydrogenation of N- and O-Containing Heterocycles Including Pyridines with H₃N–BH₃ Under the Catalysis of the Homogeneous Ruthenium Precatalyst

Organic Letters, Journal Year: 2024, Volume and Issue: 26(4), P. 866 - 871

Published: Jan. 25, 2024

In this study, we report a transfer hydrogenation protocol that utilizes borane–ammonia (H3N–BH3) as the hydrogen source and commercially available RuCl3·xH2O precatalyst for selective aromatic reduction of quinolines, quinoxalines, pyridines, pyrazines, indoles, benzofurans, furan derivatives to form corresponding alicyclic heterocycles in good excellent isolated yields. Applications straightforward include efficient preparation useful key pharmaceutical intermediates, such donepezil flumequine, including biologically active compound.

Language: Английский

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Electrochemical Dearomative Spirocyclization of N-Acyl Thiophene-2-sulfonamides

Organic Letters, Journal Year: 2022, Volume and Issue: 24(34), P. 6321 - 6325

Published: Aug. 22, 2022

The Friedel–Crafts type alkylation of C2-tethered thiophenes has been reported to be nonregioselective. Taking advantage the highly regioselective 5-exo-trig spirocyclization an electrochemically generated amidyl radical, we have unraveled electrochemical dearomative N-acyl thiophene-2-sulfonamides. Various nucleophilic agents, including carboxylates, alcohols, and fluoride, are readily incorporated afford remotely functionalized spirocyclic dihydrothiophenes, their novel scaffolds shown exhibit promising antitumor activities.

Language: Английский

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CuI nanoparticles-immobilized on a hybrid material composed of IRMOF-3 and a sulfonamide-based porous organic polymer as an efficient nanocatalyst for one-pot synthesis of 2,3-disubstituted benzo[b]furans

Arabian Journal of Chemistry, Journal Year: 2023, Volume and Issue: 16(8), P. 104975 - 104975

Published: May 13, 2023

This study was conducted to synthesize and characterize a new polymer/metal–organic framework (MOF) stabilizer via the reaction between sulfonamide-triazine-based porous organic polymer (poly(sulfonamide-triazine)) (PSTA) an amino-functionalized zinc metal–organic (IRMOF-3). Next, prepared nanocomposites (IRMOF-3/PSTA/Cu) were modified using copper iodide nanoparticles (CuI NPs). The composites characterized by FT-IR, XRD, EDX, N2 adsorption–desorption, TGA, SEM, TEM, XPS analysis. Finally, application of investigated through one-pot synthesis 2,3-disubstituted benzo[b]furans. To this end, alkyne, salicylaldehydes, amines subjected three-component domino reaction. All products obtained in high turnover frequency (TOF) up 142.42, suggesting catalyst's selectivity activity mentioned reactions. synthesized nanocatalyst is reusable seven times with no considerable catalytic efficiency loss. Overall, yields products, nanocatalyst's facile recovery, short time, wide substrate scopes make procedure eco-friendly, practical, economically justified.

Language: Английский

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Iron-Catalyzed Photoredox Intermolecular Dearomatization of Benzothiazoles with Alkanes

ACS Sustainable Chemistry & Engineering, Journal Year: 2023, Volume and Issue: 11(35), P. 13142 - 13148

Published: Aug. 24, 2023

Benzothiazolines, with their versatile nature, serve as fundamental building blocks for the synthesis of significant biological compounds. However, methods preparation benzothiazolines from readily available starting materials are limited. An efficient benzothiazoline via photoredox-catalyzed dearomatization benzothiazole derivatives has been achieved at room temperature. This catalysis proceeds a ligand to metal charge transfer process, and FeCl3 plays dual role an indirect HAT reagent reducing agent. methodology can be conveniently scaled up, most alkylated products purified without chromatography. In addition, this process exhibited advantages low cost, high reaction efficiency, mild conditions.

Language: Английский

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A Tandem Route toward Isoxazolidine Fused Phospholene Skeleton Involving Dearomative [3+2] Cycloaddition of P‐Heteroarenes and Nitrones

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

Published: Feb. 19, 2025

Comprehensive Summary The demands for effective assembly of structurally complex molecular scaffolds from simple starting materials are continuously growing along with the development organic chemistry. We have developed a tandem approach that assembles β ‐chloroethylphosphane, alkynyl imines (or ketones), and nitrones into isoxazolidine fused phospholene through sequential process involving phospha‐Michael addition, intramolecular cyclization, dearomatizing [3+2] cycloaddition reactions. isoxazolidine‐fused has three heteroatoms, including junction phosphorus atom. After removing coordinated tungsten group, these compounds can serve as potential P‐stereogenic ligands may biological activities. Contrary to pyrroles furans, aromatic 2‐phosphapyrroles 2‐phosphafurans good 2π‐electron candidates in dearomative reactions due poor overlap 2p‐3p orbitals C=P moiety.

Language: Английский

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Synthesis of Benzofuro[3,2-b]indol-3-one Derivatives via Dearomative (3 + 2) Cycloaddition of 2-Nitrobenzofurans and para-Quinamines

Molecules, Journal Year: 2024, Volume and Issue: 29(5), P. 1163 - 1163

Published: March 5, 2024

An efficient dearomative (3 + 2) cycloaddition of para-quinamines and 2-nitrobenzofurans has been developed. This reaction proceeds smoothly under mild conditions affords a series benzofuro[3,2-b]indol-3-one derivatives in good to excellent yields (up 98%) with perfect diastereoselectivities (all cases > 20:1 dr). The scale-up synthesis versatile derivatizations demonstrate the potential synthetic application protocol. A plausible mechanism is also proposed account for observed process. work represents first instance N-triggered 2-nitrobenzofurans.

Language: Английский

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Dearomatization of Nitro(hetero)arenes through Annulation

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(18)

Published: April 5, 2022

Abstract Dearomatization reactions employing simple aromatic compounds have showcased remarkable progress in the recent decade and emerged as one of most straightforward powerful tools for creation highly functionalized, three‐dimensional molecular frameworks commonly encountered medicinal chemistry life sciences. Among use, nitro(hetero)arenes, which feature a less pronounced character due to presence electron‐withdrawing nitro group, been extensively used different types dearomatization reactions. The dearomative annulation reaction serves versatile method construction complex polycyclic systems. This overview presents brief summary impressive advances nitro(hetero)arenes provides some inspirations future research.

Language: Английский

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