13C NMR substituent-induced chemical shifts in 4-(substituted phenyl)-3-phenyl-1,2,4-oxadiazol-5(4H)-ones (thiones)
作者:Yesim Saniye Kara
DOI:10.1016/j.saa.2015.04.081
日期:2015.10
4-(substituted phenyl)-3-phenyl-1,2,4-oxadiazol-5(4H)-ones and ten 4-(substituted phenyl)-3-phenyl-1,2,4-oxadiazol-5(4H)-thiones were synthesized. These oxadiazole derivatives were characterized by IR, (1)H NMR, (13)C NMR and elemental analyses. Their (13)C NMR spectra were measured in Deuterochloroform (CDCl3). The correlation analysis for the substituent-inducedchemicalshift (SCS) with Hammett substituent
Tuning chemoselectivity in <i>O</i>-/<i>N</i>-arylation of 3-aryl-1,2,4-oxadiazolones with <i>ortho</i>-(trimethylsilyl)phenyl triflates <i>via</i> aryne insertion
作者:Lijing Zhou、Hongji Li、Wenge Zhang、Lei Wang
DOI:10.1039/c8cc00124c
日期:——
A finely tunable chemoselectivity in arylation of 3-aryl-1,2,4-oxadiazolones with ortho-(trimethylsilyl)phenyl triflates is reported, including silver-catalysed O-arylation and metal-free N-arylation.
Copper‐Catalyzed Selective N‐Arylation of Oxadiazolones by Diaryliodonium Salts
作者:Natalia S. Soldatova、Artem V. Semenov、Kirill K. Geyl、Sergey V. Baykov、Anton A. Shetnev、Anna S. Konstantinova、Mikhail M. Korsakov、Mekhman S. Yusubov、Pavel S. Postnikov
DOI:10.1002/adsc.202100426
日期:2021.7.20
Here, we report the method for copper-catalyzed N-arylation of diverse oxadiazolones by diaryliodoniumsalts under mild conditions in high yields (up to 92%) using available CuI as a catalyst. The developed method allows utilizing both symmetric and unsymmetric diaryliodoniumsalts bearing auxiliary groups such as 2,4,6-trimethoxyphenyl (TMP). We found that the steric effects in aryl moieties determined
在这里,我们报告了使用可用的 CuI 作为催化剂在温和条件下以高产率(高达 92%)通过二芳基碘盐对不同恶二唑酮进行铜催化 N-芳基化的方法。所开发的方法允许使用带有辅助基团(例如 2,4,6-三甲氧基苯基 (TMP))的对称和不对称二芳基碘盐。我们发现芳基部分的空间效应决定了 1,2,4-oxadiazol-5(4 H )-ones的 N-和 O-芳基化的化学选择性。甲基取代的二芳基碘盐显示出作为选择性芳基化试剂的巨大潜力。结构研究表明 1,2,4-oxadiazol-5(4 H)-对空间位阻二芳基碘鎓盐的芳基化的影响。还证明了所提出方法的合成应用对 1,3,4-恶二唑-2(3 H )-酮和 1,2,4-恶二唑-5-硫醇的选择性芳基化。
A convenient one-pot synthesis of <i>N</i>-substituted amidoximes and their application toward 1,2,4-oxadiazol-5-ones
The first direct one-pot approach for the synthesis of N-substituted amidoximes from secondary amides or the intermediate amides has been developed. Through the Ph3P–I2-mediated dehydrative condensation, a variety of N-aryl and N-alkyl amidoximes (R1(CNOH)NHR2, where R1 or R2 = aryl, alkyl, or benzyl) were readily afforded under mild conditions and short reaction times. The synthetic application of
this paper we report the results obtained by treating some selected hydroxamic acids with diazomethane in ethereal media. The multitask reagent diazomethane was used either as a base to induce deprotonation of the chosen hydroxamic acids or as conjugated acid which undergoes one-pot methylation processes of the generated anions. Product distributions clearly showed that a high site selectivity is expressed