论文部分内容阅读
作为复杂谱图的解析和结构测定的一个有效辅助手段,位移试剂已在核磁共振实验中得到了广泛的应用。与常用的镧系元素的β-二酮络合物相比,四氯化铀作为位移试剂有许多优点。它不含氢、碳、氟等,对~1H、~(13)C、~(19)F NMR谱无干扰。U(Ⅳ)外层电子结构为5 f~2,与Pr(Ⅲ)相似,可以与Lewis碱生成各种加合物,在作用物的核磁共振谱中产生诱导位移。UCl_4的制备简单,成本较低,极易溶于水和某些极性有机溶剂,如醇类、乙酸、丙酮等。
As an effective adjunct to the analysis and structural determination of complex spectra, displacement reagents have been widely used in NMR experiments. Uranium tetrachloride has many advantages as a shift reagent compared to the commonly used lanthanide β-diketone complexes. It does not contain hydrogen, carbon, fluorine and so on, ~ 1H, ~ (13) C, ~ (19) F NMR spectra without interference. The electronic structure of U (Ⅳ) outer layer is 5 f ~ 2. Similar to Pr (Ⅲ), various adducts can be formed with Lewis base to induce displacement in the nuclear magnetic resonance spectrum of the active species. UCl_4 preparation is simple, low cost, easily soluble in water and some polar organic solvents, such as alcohols, acetic acid, acetone and so on.