Formation and Intramolecular Capture of α-Imino Gold Carbenoids in the Au(I)-Catalyzed [3 + 2] Reaction of Anthranils, 1,2,4-Oxadiazoles, and 4,5-Dihydro-1,2,4-Oxadiazoles with Ynamides DOI Open Access

Ioannis Stylianakis,

Iraklis Litinas,

Antonios Kolocouris

et al.

Catalysts, Journal Year: 2022, Volume and Issue: 12(8), P. 915 - 915

Published: Aug. 19, 2022

α-Imino gold carbenoid species have been recognized as key intermediates in a plethora of processes involving gold-activated alkynes. Here, we explored the pathways Au(I)-catalyzed [3 + 2] reaction between mild nucleophiles: anthranil, 1,2,4-oxadiazole, or 4,5-dihydro-1,2,4-oxadiazole, and an ynamide, PhC≡C-N(Ts)Me, proceeding via formation aforementioned α-imino carbene intermediate which, after intramolecular capture, regioselectively produces 2-amino-3-phenyl-7-acyl indoles, N-acyl-5-aminoimidazoles, N-alkyl-4-aminoimidazoles, respectively. In all cases, regioselectivity substituents at 2, 3 7-acyl-indole ring 4, 5 substituted imidazole is decided first transition state, attack nitrogen on C1 C2 carbon activated ynamide. A subsequent steep energy drop furnishes carbene. These features are more pronounced for anthranil 4,5-dihydro-1,2,4-oxadiazole reactions. Strikingly, significant due to unstable carbene, which spontaneous benzaldehyde elimination converted stabilized one. Compared 1,2,4-oxadiazoles 4,5-dihydro-1,2,4-oxadiazoles found be significantly complex than anticipated original research. For instance, compared five-member from one competitive route involves consisting four-member condensed with three-member ring, metathesis expansion led ring.

Language: Английский

Efficient Synthesis, Structural Characterization, Antibacterial Assessment, ADME-Tox Analysis, Molecular Docking and Molecular Dynamics Simulations of New Functionalized Isoxazoles DOI Creative Commons

Aziz Arzine,

Hanine Hadni, Khalid Boujdi

et al.

Molecules, Journal Year: 2024, Volume and Issue: 29(14), P. 3366 - 3366

Published: July 17, 2024

This work describes the synthesis, characterization, and in vitro silico evaluation of biological activity new functionalized isoxazole derivatives. The structures all compounds were analyzed by IR NMR spectroscopy. 4c 4f further confirmed single crystal X-ray their compositions unambiguously determined mass spectrometry (MS). antibacterial effect isoxazoles was assessed against Escherichia coli, Bacillus subtilis, Staphylococcusaureus bacterial strains. Isoxazole 4a showed significant E. coli B. subtilis compared to reference antibiotic drugs while 4d also exhibited some effects. molecular docking results indicate that synthesized exhibit strong interactions with target proteins. Specifically, displayed a better affinity for S. aureus, comparison drugs. dynamics simulations performed on strongly support stability ligand–receptor complex when interacting active sites proteins from subtilis. Lastly, Absorption, Distribution, Metabolism, Excretion Toxicity Analysis (ADME-Tox) reveal molecules have promising pharmacokinetic properties, suggesting favorable druglike properties potential therapeutic agents.

Language: Английский

Citations

9
Ruthenium-catalyzed oxidative coupling of vinylene carbonate with isoxazoles: access to fused anthranils DOI
Pravin Kumar, Manmohan Kapur

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(28), P. 4476 - 4479

Published: Jan. 1, 2022

A ruthenium-catalyzed oxidative coupling of vinylene carbonate with isoxazoles has been developed to achieve the direct C-H formylmethylation a diverse array arylisoxazoles utilizing isoxazole ring as directing group. simple manipulation established reaction conditions leads formation fused-anthranils. Importantly, functions both formylmethyl cation equivalent through decarboxylation process and an acetylene equivalent. Control experiments were conducted elucidate plausible mechanism. This methodology is expected provide facile expeditious approach for synthesis

Language: Английский

Citations

25
Structural Evidence for Aromatic Heterocycle N–O Bond Activation via Oxidative Addition DOI
Michael K. Bogdos, Patrick Müller, Bill Morandi

et al.

Organometallics, Journal Year: 2023, Volume and Issue: 42(3), P. 211 - 217

Published: Jan. 3, 2023

Many methods report the scission of N–O bonds aromatic heterocycles and their subsequent functionalization. Oxidative addition is one presumed pathways through which bond activation with transition metals achieved. We first well-defined pathway (benz)isoxazole's oxidative addition. also provide control experiments, show that may be broken by strong inorganic reductants. These results highlight are susceptible to both reduction addition, has important implications for catalysis. Exploring reactivity these complexes toward a series electrophiles leads discovery Staudinger-type β-lactam synthesis upon reaction ketene. Finally, we demonstrate choice different metal/ligand combinations allows selective into either C–I or in presence other.

Language: Английский

Citations

10
Rapid synthesis of fully substituted arylideneisoxazol-5(4H)-one using zinc oxide nanoparticles DOI

Shiva Aslanpour,

Hamzeh Kiyani

Research on Chemical Intermediates, Journal Year: 2023, Volume and Issue: 49(10), P. 4603 - 4619

Published: July 9, 2023

Language: Английский

Citations

10
Ru(ii) catalyzed chelation assisted C(sp2)–H bond functionalization along with concomitant (4 + 2) annulation DOI
Anindita Sarkar, Moumita Saha, Asish R. Das

et al.

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

Citations

9
Advances in transition metal-catalyzed C–H amination strategies using anthranils DOI
Yogesh N. Aher, Nilanjan Bhaduri, Amit B. Pawar

et al.

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(44), P. 8794 - 8812

Published: Jan. 1, 2023

Modern times have witnessed an uprise in the synthesis and derivatization of nitrogen-containing fused heterocycles. Amination reactions involving nitrene chemistry always been most convenient choice for incorporation a nitrogen atom molecule. The utilization open species harnesses harsh conditions. Hence, transition metal-catalyzed C-H amination using aminating agents attractive choice. Electrophilic are well exploited due to their desirable reaction Out all, anthranils paved way forward utility simultaneously forming two new functional groups (amine carbonyl). follows metal-nitrenoid pathway. Often, has followed by Lewis acid or metal-mediated intramolecular cyclization directly produce This review broadly demonstrates as agent reactions. focus given scope, limitations, mechanistic understanding such electrophilic agent, anthranil, with metals.

Language: Английский

Citations

9
Asymmetric electrophilic functionalization of amino-substituted heteroaromatic compounds: a convenient tool for the enantioselective synthesis of nitrogen heterocycles. DOI
Gonzalo Blay, Alicia Monleón, Marc Montesinos‐Magraner

et al.

Chemical Communications, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

The catalytic asymmetric electrophilic functionalization of the less reactive N-heteroaromatic compounds has been reported using approach introduction an exocyclic amino substituent.

Language: Английский

Citations

2
Ring-Opening Fluorination of Isoxazoles DOI
Masaaki Komatsuda,

Hugo Ohki,

Hiroki Kondo

et al.

Organic Letters, Journal Year: 2022, Volume and Issue: 24(17), P. 3270 - 3274

Published: April 26, 2022

A ring-opening fluorination of isoxazoles has been developed. Upon treatment with an electrophilic fluorinating agent (Selectfluor), followed by deprotonation leads to tertiary fluorinated carbonyl compounds. This method features mild reaction conditions, good functional group tolerance, and a simple experimental procedure. Diverse transformations the resulting α-fluorocyanoketones were also demonstrated, furnishing variety

Language: Английский

Citations

10
N‐Chlorosuccinimide‐Promoted One‐Pot Synthesis of Substituted 4,5‐Dihydroisoxazole‐5‐methanols in Aqueous Medium DOI
Yunfei Jia, Keyume Ablajan

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(2), P. 244 - 251

Published: Jan. 6, 2023

Abstract Herein, a catalyst‐free method for synthesizing 4,5‐dihydroisoxazole‐5‐methanols is proposed, whereby isoxazolines are constructed through the NCS‐mediated 1,3‐dipolar cycloaddition reaction of aldoximes and allyl alcohol in presence K 2 CO 3 at room temperature via one‐pot route. The was achieved water medium to introduce low‐cost direct protocol isoxazolines. This offers advantages including use an oxidant‐free transition metal‐free approach, broad scope aldoxime substrates, room‐temperature reaction, good higher yields (42–92%), involvement gram‐scale synthesis. magnified image

Language: Английский

Citations

5
Synthesis of Arylideneisoxazol-5-ones Catalyzed by Sodium Cyclamate DOI Open Access
Hamzeh Kiyani

Heterocycles, Journal Year: 2023, Volume and Issue: 106(7), P. 1187 - 1187

Published: Jan. 1, 2023

The three-component reactions using aryl aldehydes, hydroxylamine hydrochloride, and β-ketoesters (ethyl acetoacetate, ethyl 4-chloro-3-oxobutanoate, 3-oxohexanoate) as available precursors were performed to synthesize arylideneisoxazol-5-ones.The experiments have been catalyzed sodium cyclamate high yields of products obtained under green conditions at room temperature.Relatively shorter reaction time, free from the use organic medium, simplicity method, formation pure without chromatographic methods, inexpensive are among advantages this method.Heating other devices for energy supply not required.Also, in process, water a medium is line with principles chemistry.In world heterocycles, isoxazoles their special place, probably because diversity also many applications. 1The isoxazole cyclic system documented an important moiety wide variety pharmaceutical drugs. 2 According literature, they ranked 31st 351 ring systems found synthetic medicinal compounds. 3 core naturally occurring nature, agrochemicals, propellant plasticizers, explosives well versatile building blocks synthesis. 4The can be observed liquid crystalline compounds interesting optoelectronic properties. 5Among most studied isoxazoles, isoxazol-5(4H)-ones privileged heterocycles that range drugs, natural products, biologically active compounds, great interest. 6Many properties such antiviral, anti-inflammatory, antioxidant, anticancer, antimicrobial, antifungal, anti-Alzheimer's disease, antineoplastic, anti-tuberculosis belong category arylideneisoxazol-5-ones. 7 Besides,

Language: Английский

Citations

5