Puentes Cira Mollings, Wenzel Thomas J
Department of Chemistry, Bates College, Lewiston, Maine 04240 USA.
Beilstein J Org Chem. 2017 Jan 6;13:43-53. doi: 10.3762/bjoc.13.6. eCollection 2017.
The utility of phosphated α-, β- and γ-cyclodextrins as water-soluble chiral NMR solvating agents for cationic substrates is described. Two sets of phosphated cyclodextrins, one with degrees of substitution in the 2-6 range, the other with degrees of substitution in the 6-10 range, are examined. Results with 33 water-soluble cationic substrates are reported. We also explored the possibility that the addition of paramagnetic lanthanide ions such as praseodymium(III) and ytterbium(III) further enhances the enantiomeric differentiation in the NMR spectra. The chiral differentiation with the phosphated cyclodextrins is compared to prior results obtained with anionic carboxymethylated cyclodextrins. There are a number of examples where a larger differentiation is observed with the phosphated cyclodextrins.
描述了磷酸化的α-、β-和γ-环糊精作为阳离子底物的水溶性手性核磁共振溶剂化剂的效用。研究了两组磷酸化环糊精，一组取代度在2-6范围内，另一组取代度在6-10范围内。报告了33种水溶性阳离子底物的结果。我们还探讨了添加顺磁性镧系离子（如镨(III)和镱(III)）是否能进一步增强核磁共振谱中的对映体区分。将磷酸化环糊精的手性区分与先前使用阴离子羧甲基化环糊精获得的结果进行了比较。有许多例子表明，使用磷酸化环糊精观察到了更大的区分度。
