The effect of europium tris 3-(heptafluoropropylhydroxymethylene)-(+)-camphorate on the hydrogen signal chemical shift of a series of bi-1,2,3-triazoles was studied by 1H NMR, displaying a signal discrimination which indicates the formation of atropisomers in these molecules. In addition, the rotational barrier around the C5−C5’ bond for bi-1,2,3-triazoles was calculated using the DFT (B3LYP) method
通过1 H NMR研究了三 3-(七
氟丙基
羟基亚甲基)-(+)-
樟脑酸
铕对一系列双
1,2,3-三唑的氢信号
化学位移的影响,显示出信号辨别表明形成这些分子中的阻转异构体。此外,使用具有 6-31G** 基组的 DFT (B3LYP) 方法计算双
1,2,3-三唑的 C5-C5' 键周围的旋转势垒,揭示了显着的能垒(高达 34 kcal/ mol) 在 204-206° 二面角和低阻转异构体相互转化。这些元素允许直接识别源自
铜催化的
叠氮化物-
炔烃环加成的手性双
1,2,3-三唑。