Studies on Azole-to-Azole Interconversion − An Interesting Case of Absence of a “Primary Steric Effect” in the Ring-Degenerate Equilibration betweenortho-Substituted 3-Aroylamino-5-methyl-1,2,4-oxadiazoles and 3-Acetylamino-5-aryl-1,2,4-oxadiazoles in Methanol
作者:Silvestre Buscemi、Vincenzo Frenna、Andrea Pace、Nicolò Vivona、Barbara Cosimelli、Domenico Spinelli
DOI:10.1002/1099-0690(200204)2002:8<1417::aid-ejoc1417>3.0.co;2-g
日期:2002.4
in CD3OD and in tBuOK/CD3OD. The components of the electronic effect of the substituent on the benzene ring show different contributions depending on whether the equilibrium between neutral (strong prevalence of the “proximity polar effect”) or anionic species (balance between “ordinary and proximity polar effects”) is considered. The “primary steric effect” does not significantly affect the reactivity
已通过 1H NMR 在 CD3OD 和 tBuOK/CD3OD 中研究了标题反应。苯环上的取代基的电子效应分量表现出不同的贡献,这取决于是否考虑中性(“近极性效应”的强烈流行)或阴离子物种(“普通极性和近极性效应”之间的平衡)之间的平衡. “初级空间效应”不会显着影响反应性,可能是因为内部酰胺共轭的重要性。对于邻甲氧基衍生物,观察到了有趣的“特殊”邻近效应。(© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)