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

Copper Nitrate‐Mediated Selective Bond Cleavage of Alkynes: Diverse Synthesis of Isoxazoles† DOI
Jianan Liu,

Kaijing Zhou,

Shaobo Sun

et al.

Chinese Journal of Chemistry, Journal Year: 2023, Volume and Issue: 41(23), P. 3299 - 3304

Published: Aug. 3, 2023

Comprehensive Summary An unprecedented copper nitrate‐mediated bond cleavage of alkynes was developed for the modular synthesis isoxazoles, where either C—S or C≡C triple cleaved selectively. Substituents attached to bonds could differentiate chemical and reaction pathways disparately. Various transformations products illustrate promising applications given protocols.

Language: Английский

Citations

5
Copper-catalyzed crosscoupling of vinyl nitrenes and CF3-carbenes to synthesize CF3-2-azadienes DOI

Yongjuan Jiao,

Tao Wu, Xinyu Zhang

et al.

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 11(1), P. 67 - 73

Published: Nov. 7, 2023

A unique and efficient copper catalytic system has been established for the synthesis of fluorinated 2-azadienes from isoxazoles CF 3 - N -tosylhydrazones via crosscoupling reactions vinyl nitrenes with fluoroalkyl carbenes.

Language: Английский

Citations

4
Radical Nitrososulfonation of Propargyl Alcohols: Thiazolidine-2,4-dione-Assisted Synthesis of 5-Alykyl-4-sulfonylisoxazoles DOI
Tomoki Nakano,

Nami Kousaka,

A. NAKAYAMA

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(9), P. 1753 - 1757

Published: Feb. 27, 2024

In this study, we discover a good NO/HNO precursor, N-hydroxypyridinesulfonamide, and the regioselective radical nitrososulfonylation reaction of propargyl alcohols. Direct unique isoxazole synthesis afforded good-to-high yield 5-alkyl-3-aryl-4-pyridinesulfonylisoxazoles. Copper-catalyzed aerobic oxidation could efficiently proceed in presence thiazolidine-2,4-dione. This work provides powerful method for functionalization alkyl-substituted isoxazoles explores new investigation route drug–drug discovery.

Language: Английский

Citations

1
Access to Isoxazoles via Photo-oxygenation of Furan Tethered α-Azidoketones DOI

Uma Devi Newar,

Sylvia Jaya Kumar,

Anupriya Borah

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(17), P. 12378 - 12386

Published: Aug. 22, 2024

Photocatalyst-free visible light-enabled direct oxygenation of furan-tethered α-azidoketones was studied. The reaction yielded various products depending on the substituents, with isoxazoles forming as major products. findings suggest that singlet oxygen generated during and reacted in a [4 + 2] fashion to yield endoperoxides, which rearranged multiple ways generate isoxazoles. Some synthesized were evaluated α-glucosidase inhibitors, three them 5bi, 5bj, 5bl exhibited good activity IC50 values 454.57 ± 29.34, 147.84 2.28, 272.58 42.06 μM, respectively, when compared standard drug acarbose (IC50 = 1224.33 126.72 μM).

Language: Английский

Citations

1
Isoxazole as a nitrile synthon: en routes to the ortho-alkenylated isoxazole and benzonitrile with allyl sulfone catalyzed by Ru(ii) DOI
Pritishree Panigrahi, Subhendu Ghosh, Tamanna Khandelia

et al.

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(70), P. 10536 - 10539

Published: Jan. 1, 2023

A Ru(II) catalyzed regioselective Heck-type C-H olefination of isoxazole with unactivated allyl phenyl sulfone is revealed. The solvent DCM offers dual sp2-sp2 activation via an N-directed strategy, leading to ortho-olefinated isoxazoles exclusive E-selectivity. On the other hand, in DCE solvent, serves as nitrile synthon and leads o-olefinated benzonitrile. At a higher temperature (110 °C) DCE, after ortho-olefination mediated cleavage delivered functionality.

Language: Английский

Citations

3
Catalytic asymmetric reaction of isoxazoles and benzisoxazoles DOI Creative Commons
Xin‐Qi Zhu,

Jia-Juan He,

Bo Zhou

et al.

Cell Reports Physical Science, Journal Year: 2023, Volume and Issue: 4(11), P. 101645 - 101645

Published: Oct. 30, 2023

Isoxazoles and their derivatives have been verified to be versatile building blocks crucial intermediates for the synthesis of a range useful N-containing molecules, especially valuable N-heterocycles. However, catalytic asymmetric reaction isoxazole has rarely explored, there is no systematic summary date. In this perspective, we summarize recent advances in isoxazoles benzisoxazoles according different types reactions: (1) transition-metal-catalyzed ring contraction isoxazoles, (2) copper-catalyzed hydroamination alkenes alkynes with benzisoxazoles, (3) formal annulations benzisoxazoles. Finally, propose remaining challenges opportunities future breakthroughs area.

Language: Английский

Citations

3
Copper Nanoparticles on Montmorillonite K-10: A Versatile Catalyst for the One-Pot Synthesis of 3,5-Disubstituted Isoxazoles Using Various Methodologies DOI
Gabriel Radivoy, Santiago Stabile,

Esteban E. Bjerg

et al.

Synthesis, Journal Year: 2023, Volume and Issue: 56(02), P. 281 - 292

Published: Oct. 17, 2023

Abstract A readily prepared and versatile heterogeneous catalyst composed of copper nanoparticles supported on montmorillonite K-10 (CuNPs/MK-10) has proven to be highly effective in catalyzing the synthesis isoxazoles through various one-pot methodologies with high atom economy. These allow for use available starting materials, including aldehydes alkynes 1,3-dipolar cycloaddition reactions, as well via cycloisomerization ynones. Additionally, CuNPs/MK-10 promoted situ formation ynones an acyl Sonogashira coupling. Furthermore, a three-step methodology was also developed, from carboxylic acids involving generation chlorides.

Language: Английский

Citations

2
Synthesis of acridinesviacopper-catalyzed amination/annulation cascades between arylboronic acids and anthranils DOI
Yuge Li, Liang Xu, Yu Wei

et al.

Organic & Biomolecular Chemistry, Journal Year: 2022, Volume and Issue: 20(48), P. 9742 - 9745

Published: Jan. 1, 2022

The direct conversion of aryl boronic acids and anthranils to acridines has been realized herein, via the catalysis copper species under acidic conditions.

Language: Английский

Citations

4
Synthetic utility of styrenes in the construction of diverse heterocycles via annulation/cycloaddition DOI
Bubul Das, Nikita Chakraborty, Kamal Krishna Rajbongshi

et al.

Tetrahedron, Journal Year: 2023, Volume and Issue: 134, P. 133270 - 133270

Published: Jan. 20, 2023

Language: Английский

Citations

2
5‐Styrylisoxazoles: π‐Conjugated System with Fluorescent Properties and Bioactivity DOI
Kirill S. Sadovnikov,

Dmitry A. Vasilenko,

Yulia A. Gracheva

et al.

ChemistrySelect, Journal Year: 2023, Volume and Issue: 8(20)

Published: May 24, 2023

Abstract A simple two‐step protocol for the synthesis of 3‐aryl/hetaryl‐4‐nitro‐5‐styrylisoxazole was elaborated. large series novel 5‐styrylisoxazoles (36 compounds) containing various substituents at positions 3 and 5 isoxazole cycle obtained. The title compounds revealed fluorescent properties in visible region, possessing emission maximum up to 610nm. effect solvatochromism chemosensor towards a number metal cations were demonstrated. Cytotoxic activity against MCF‐7 (breast carcinoma), HCT‐116 (colon A549 (pulmonary carcinoma) WI38 (fibroblasts from lung tissue) cell lines tested toxicity concentration range 10–100 μM found several compounds.

Language: Английский

Citations

2