A reaction involving an efficient NBS-mediated oxidative N‒O bond formation has been established for the synthesis of 1,2,4-oxadiazoles from readily accessible N-acyl amidines. The features of this synthetic method include simplicity of operation, mild reaction conditions, short reaction times, high yields, and eco-friendliness. The reaction also works well with crude N-acyl amidines obtained by amidation
temperature in the superbase system KOH/DMSO represents a simple and efficient way to 5-alkenyland 5-styryl-1,2,4-oxadiazoles. This method is suitable for the preparation of 5-(4-vinylphenyl)-1,2,4-oxadiazoles as well. Results of the antimicrobial tests demonstrated that the synthesized compounds exhibit a moderate antimicrobial effect against E.coli, S.aureus and C.albicans strains.
Δ2-1,2,4-Oxadiazoline durch Kondensation von Amidoximen mit Ketonen und Aldehyden
作者:Jürgen Lessel
DOI:10.1002/ardp.19933260703
日期:——
Ketone und aromatische Aldehyde cyclisieren in Eisessig mit aromatischen Amidoximen des Typs 1 zu Δ2‐1,2,4‐Oxadiazolinen 3, in neutralen Solventien hingegen bleibt die Reaktion aus. Dieses unterschiedliche Verhalten wird durch MNDO‐Berechnungen erklärt; als reaktive Spezies sind die protonierten Carbonylverbindungen anzunehmen.
One-Pot Synthesis of 3,5-Disubstituted 1,2,4-Oxadiazoles Using Catalytic System NaOH‒DMSO
作者:V. E. Pankrat’eva、T. V. Sharonova、M. V. Tarasenko、S. V. Baikov、E. R. Kofanov
DOI:10.1134/s1070428018080213
日期:2018.8
One-pot convenient process was developed for the production of 3,5-disubstituted 1,2,4-oxadiazoles by reaction of amidoximes with anhydrides or acyl chlorides in a system NaOH‒DMSO. The reaction proceeds at room temperature with high yields.
One-pot synthesis of 3,5-disubstituted 1,2,4-oxadiazoles containing an alkenyl moiety
作者:Vera V. Sidneva、Marina V. Tarasenko、Evgeniy R. Kofanov
DOI:10.1007/s10593-022-03096-5
日期:2022.7
A one-pot method was developed for the preparation of 3,5-disubstituted 1,2,4-oxadiazoles containing an alkenyl fragment, which entails the preparation of O-acylamidoximes and their subsequent cyclization using N,N′-dimethylacetamide as a solvent. The proposed method allows to significantly reduce the overall synthesis time by carrying out all steps sequentially in a single reactor, avoiding the step