Electrochemical enaminone C–H thiolation/C–N amination cascade for thiazole synthesis and its diastereoselective dearomatization

Green Chemistry, Год журнала: 2022, Номер 24(13), С. 5058 - 5063

Опубликована: Янв. 1, 2022

The electrochemical annulation of enaminones/analogous enamines and thioureas providing 2-aminothiazoles has been realized. Modulating the electrolyte enables diastereoselective synthesis 4,5-dialkoxyl thiazolines by dearomatization.

Язык: Английский

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Copper‐Catalyzed Oxidative [1+2+1+2] Cascade Cyclization of N,N‐Dimethyl Enaminones with Benzylamines: A Facile Access to Functionalized 1,4‐Dihydropyridines

Chemistry - A European Journal, Год журнала: 2023, Номер 29(28)

Опубликована: Фев. 24, 2023

Using benzylamines as the C4 source of 1,4-dihydropyridines (1,4-DHPs), a Cu-catalyzed oxidative [1+2+1+2] cascade cyclization for synthesis 1,4-DHPs was firstly developed. A broad range easily available N,N-dimethyl enaminones and are employed smoothly to provide diverse with high efficiency. This method is performed by one-pot C(sp3 )-H bond functionalization/C(sp3 )-N cleavage/cyclization strategy form simultaneously two )-C(sp2 ) bonds, C(sp2 1,4-DHP ring.

Язык: Английский

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Design, synthesis, in silico and biological evaluations of novel polysubstituted pyrroles as selective acetylcholinesterase inhibitors against Alzheimer’s disease

Scientific Reports, Год журнала: 2022, Номер 12(1)

Опубликована: Сен. 8, 2022

Abstract The objective of this study was to design new polysubstituted pyrrole derivatives as selective acetylcholinesterase (AChE) inhibitors target Alzheimer's disease. In context, a highly efficient, one-pot, sequential, multi-component synthesis diverse range pyrroles developed through sequential domino strategy by the condensation amines with 1,1-bis(methylthio)-2-nitroethene (BMTNE), Knovenagle reaction arylglyoxals malono and subsequent Michael addition intramolecular cyclization in EtOH at reflux . Thirty-nine synthesized compounds were evaluated AChE butyrylcholinesterase (BChE) inhibitors. Among compounds, compound 4ad (IC 50 = 2.95 ± 1.31 µM) most potent inhibitor no significant inhibition against BChE. A kinetic revealed that inhibited an uncompetitive mode. Based on molecular modeling study, due its small size properly fitted into active site compared BChE stabilized H-bond hydrophobic interactions critical residues binding pocket. Consequently, it proposed derivative can be ideal lead candidate AD simple practical operation synthetic procedures.

Язык: Английский

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Rh(iii)-catalyzed cascade annulation reaction of N,N-dimethyl enaminones with iodonium ylides to give substituted isocoumarins

New Journal of Chemistry, Год журнала: 2023, Номер 47(26), С. 12274 - 12278

Опубликована: Янв. 1, 2023

A wide variety of isocoumarin derivatives are easily constructed via a Rh( iii )-catalyzed C–H bond activation/annulation cascade reaction.

Язык: Английский

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Synthesis of Functionalized 3‐(1H‐Isochromen)‐chromones via Ag₂O‐Catalyzed Cascade Cyclization Reaction of o‐Hydroxyarylenaminones with o‐Alkynylbenzaldehydes

Advanced Synthesis & Catalysis, Год журнала: 2022, Номер 364(24), С. 4440 - 4446

Опубликована: Дек. 2, 2022

Abstract A silver‐catalyzed protocol for the synthesis of 3‐(1 H ‐isochromen)‐chromones is described. The method involves an initial 6‐endo‐dig cyclization o ‐alkynylbenzaldehydes and domino C−H alkylation chromone annulation ‐hydroxyarylenaminones, which enables installation 1 ‐isochromen in a single structure. This synthetic strategy advantageous excellent regioselectivity, step economy, concise one‐pot methodology, gram‐scale synthesis, as well high bond‐forming efficiency. magnified image

Язык: Английский

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An Oxidative [3+2+1] Cyclization of Enaminones and N‐Alkenyl‐2‐pyrrolidinone: Access to Polysubstituted 4‐Alkylated 1,4‐dihydropyridines

Advanced Synthesis & Catalysis, Год журнала: 2023, Номер 365(8), С. 1217 - 1223

Опубликована: Март 25, 2023

Abstract An oxidative [3+2+1] cyclization of enaminones and N ‐alkenyl‐2‐pyrrolidinone is described for the synthesis 4‐alkylated 1,4‐dihydropyridines (1,4‐DHPs). By using terminal olefin as C4 source 1,4‐DHP skeleton, this synthetic strategy provides a series 1,4‐DHPs through 1,1‐difunctionalization/cyclization process. In protocol, two C( sp 3 )−C( 2 ) bonds )−N bond are simultaneously formed, hydrogen on newly formed methyl group skeleton confirmed possible mechanism proposed. magnified image

Язык: Английский

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Synthesis of benzo[b][1,5]diazocin-6(5H)-one derivatives via the Cu-catalysed oxidative cyclization of 2-aryl-1H-indoles with 1,1-enediamines

Chemical Communications, Год журнала: 2023, Номер 59(9), С. 1217 - 1220

Опубликована: Янв. 1, 2023

A novel protocol for the synthesis of highly functionalized benzo[b][1,5]diazocin-6(5H)-one derivatives (BDCOs, 4 and 5) from 2-aryl-1H-indoles 1,1-enediamines was developed via a complex cascade reactions including regioselective free radical oxidation, 1,2-addition imine, imine-enamine tautomerization, intramolecular cyclization, ring expansion. The reaction enabled by refluxing mixture two substrates in presence di-tert-butyl peroxide (DTBP) as an oxidant anhydrous CuI catalyst toluene under argon protection. Consequently, series BDCOs (4 were synthesized with high regioselectivity good yield. This can be used one-pot oxidative annulation rather than multi-step reaction, which is suitable both combinatorial parallel syntheses BDCOs.

Язык: Английский

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Chemoselectivity of the CuAAC/Ring Cleavage/Cyclization Reaction between Enaminones and α-Acylketenimine

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(4), С. 2190 - 2199

Опубликована: Янв. 27, 2024

Ketenimines represent an important class of reactive species, useful synthetic intermediates, and synthons. However, in general, ketenimines preferentially undergoes nucleophilic addition reactions with hydroxyl amino groups, carbon functional groups remain a less studied subset such systems. Herein, we develop straightforward syntheses pyridin-4(1H)-imines that is achieved by cyclization reacting enaminone unit α-acylketenimine which generated from the sulfonyl azides terminal ynones situ (CuAAC/Ring cleavage reaction). The cascade process starts α-C instead group, attacking electron-deficient central ketenimine, chemoselectivity unconventional products were formed intramolecular cyclization.

Язык: Английский

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Facile approach to multifunctionalized 5-alkylidene-3-pyrrolin-2-ones via regioselective oxidative cyclization of 2,4-pentanediones with primary amines and sodium sulfinates

Organic Chemistry Frontiers, Год журнала: 2022, Номер 9(15), С. 4078 - 4084

Опубликована: Янв. 1, 2022

Highly functionalized 5-alkylidene-3-pyrrolin-2-ones were efficiently synthesized via a four-component cascade cyclization/sulfonylation reaction between readily available 2,4-pentanediones, primary amines and sodium sulfinates under mild conditions.

Язык: Английский

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Synthesis of 4-Alkylated 1,4-Dihydropyridines: Fe(II)-Mediated Oxidative Cascade Cyclization Reaction of Cyclic Ethers with Enaminones

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(16), С. 11627 - 11636

Опубликована: Авг. 9, 2023

Syntheses of highly functionalized 4-alkylated 1,4-dihydropyridines (1,4-DHPs) from cyclic ethers and enaminones via iron(II)-mediated oxidative free radical cascade C(sp3)-H bond functionalization/C(sp3)-O cleavage/cyclization reaction have been first developed. This novel synthetic strategy offers an alternative method for the construction 1,4-DHPs by using esters as C4 sources, well expands application in heterocycle synthesis.

Язык: Английский

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