Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany.
Chemistry. 2022 Sep 12;28(51):e202201527. doi: 10.1002/chem.202201527. Epub 2022 Jul 21.
The pollution of groundwater with nitrate is a serious issue because nitrate can cause several diseases such as methemoglobinemia or cancer. Therefore, selective removal of nitrate by efficient binding to supramolecular hosts is highly desired. Here we describe how to make [2+3] amide cages in very high to quantitative yields by applying an optimized Pinnick oxidation protocol for the conversion of corresponding imine cages. By NMR titration experiments of the eight different [2+3] amide cages with nitrate, chloride and hydrogen sulfate we identified one cage with an unprecedented high selectivity towards nitrate binding vs. chloride (S=705) or hydrogensulfate (S>13500) in CD Cl /CD CN (1 : 3). NMR experiments as well as single-crystal structure comparison of host-guest complexes give insight into structure-property-relationships.
地下水的硝酸盐污染是一个严重的问题，因为硝酸盐会导致多种疾病，如高铁血红蛋白血症或癌症。因此，通过与超分子主体的有效结合来选择性地去除硝酸盐是非常需要的。在这里，我们描述了如何通过应用优化的 Pinnick 氧化方案，将相应的亚胺笼转化为[2+3]酰胺笼，以非常高的产率（高达定量产率）得到[2+3]酰胺笼。通过对八个不同的[2+3]酰胺笼与硝酸盐、氯化物和硫酸氢盐的 NMR 滴定实验，我们在 CDCl/CD3CN（1:3）中鉴定出一个对硝酸盐结合具有前所未有的高选择性的笼，对氯离子（S=705）或硫酸氢根（S>13500）的选择性（S>13500）。NMR 实验以及主客体配合物的单晶结构比较提供了结构-性质关系的深入了解。
