Divergent synthesis of polysubstituted isoxazoles, isoxazoline N-oxides, and dihydroisoxazoles by a one-pot cascade reaction

Date

2017-01-26

Author

Rouf, Abdul
ŞAHİN, Ertan
Tanyeli, Cihangir

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

221
views

0
downloads

An efficient one-pot synthesis of a new class of 3,4,5-trisubstituted isoxazoline N-oxides/isoxazoles and dihydroisoxazoles is developed by a green approach from aromatic and aliphatic aldehydes by controlling the reaction conditions. Aldehydes were reacted with ethyl nitroacetate in the presence of DABCO as a catalyst under ultrasonication. In aromatic aldehydes, isoxazoline N-oxides were obtained exclusively when the reaction was carried out at 40 degrees C, but raising the temperature to 80 degrees C isoxazoles were formed selectively. Aliphatic aldehydes, on the other hand, gave a mixture of isoxazoline N-oxides and dihydroisoxazoles where the ratio of these depended on the bulk of the aliphatic chain on the aldehyde. This is the first method for the synthesis of aliphatic 4-substituted-3,5-bis(ethoxycarbonyl)isoxazoline N-oxides and 4-substituted-3,5-bis(ethoxycarbonyl)-dihydroisoxazoles with good to excellent yields.

Subject Keywords

Organic Chemistry, Biochemistry, Drug Discovery

URI

https://hdl.handle.net/11511/39824

Journal

TETRAHEDRON

DOI

https://doi.org/10.1016/j.tet.2016.12.005

Collections

Department of Chemistry, Article

Suggestions

OpenMETU
Core

Reinvestigation of the synthetic and mechanistic aspects of Mn(III) acetate mediated oxidation of enones Demir, Ayhan Sıtkı; Reis, O; Igdir, AC (Elsevier BV, 2004-04-05) Mn(OAc)(3) mediated alpha'-acetoxylation of alpha,beta-unsaturated enones is reinvestigated from a synthetic and mechanistic point of view and an improved procedure based on the use of acetic acid as a co-solvent is presented. Excellent results were obtained for a variety of structurally diverse and synthetically important enones under the optimized conditions.
Asymmetric aldol addition of alpha-azido ketones to ethyl pyruvate mediated by a cinchona-based bifunctional urea catalyst Okumus, Seda; Tanyeli, Cihangir; Demir, Ayhan Sıtkı (Elsevier BV, 2014-07-30) The first asymmetric synthesis of ethyl 4-aryl-3-azido-2-hydroxy-2-methyl-4-oxobutanoates via a cinchona organocatalyst induced aldol addition of alpha-azido ketones to ethyl pyruvate has been developed. The coupling reaction under optimized conditions was carried out to furnish tetrafunctionalized synthons with enantioselectivities of up to 91:9 and enriched diastereoselectivities of up to 95:5 (syn:anti).
Synthesis of ferrocenyl quinones Zora, Metin; Acikalin, S (Elsevier BV, 2003-03-03) A squarate-based synthesis of ferrocenyl quinones is described. Thermolysis of ferrocenyl-substituted cyclobutenones, prepared from ferrocenyl cyclobutenediones and alkenyllithiums, affords hydroquinones, which furnish, upon oxidation, ferrocenyl quinones. Ferrocenyl cyclobutenediones have been prepared from known cyclo butenediones by nucleophilic addition of ferrocenyllithium followed by hydrolysis, Pd/Cu-cocatalyzed cross-coupling with (tri-n-butylstannyl)ferrocene or Friedel-Crafts alkylation with ferro...
Intermolecular heterocyclization of alkynones with 2-mercaptoacetaldehyde under metal-free conditions: synthesis of 2,3-disubstituted thiophenes Vatansever, Erol Can; Kilic, Kubra; Ozer, Merve Sinem; KOZA, GANİ; Menges, Nurettin; Balcı, Metin (Elsevier BV, 2015-09-30) A concise and regioselective approach for the synthesis of 2,3-disubstituted thiophene derivatives has been developed. The synthetic strategy relies on the reaction of an in situ generated 2-mercaptoacetaldehyde with various alkynones. Furthermore, we calculated the energy gap between the HOMO and the LUMO orbitals of all compounds and observed that the introduction of a strong electron-withdrawing group decreased the HOMO-LUMO energy gap.
Enzyme catalyzed hydroxymethylation of aromatic aldehydes with formaldehyde. Synthesis of hydroxyacetophenones and (S)-benzoins Demir, Ayhan Sıtkı; Ayhan, P; Igdir, AC; Duygu, AN (Elsevier BV, 2004-07-26) Benzaldehyde lyase from the Pseudomonas Fluorescens catalyzed reaction of aromatic aldehydes with formaldehyde providing 2-hydroxy-1-arylethan-1-one in high yields via an acyloin linkage. Kinetic resolution of rac-benzoins with formaldehyde providing (S)-benzoins and 2-hydroxy-1-arylethan-1-one via C-C bond cleavage and a bond formation reaction.

Citation Formats

A. Rouf, E. ŞAHİN, and C. Tanyeli, “Divergent synthesis of polysubstituted isoxazoles, isoxazoline N-oxides, and dihydroisoxazoles by a one-pot cascade reaction,” TETRAHEDRON, pp. 331–337, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39824.