Muñoz Marcelo A, Bucio Maria A, Joseph-Nathan Pedro
Instituto de Ciencias Químicas, Universidad Austral de Chile, Casilla 567, Valdivia, Chile.
Nat Prod Commun. 2013 Aug;8(8):1075-8.
Chiral HPLC coupled to electronic circular dichroism and laser optical rotation detection (HPLC-ECD-OR) permitted the on-line chiroptical characterization of both enantiomers of racemic flavanone (1) as ECD(-)310-OR(-)670-flavanone and ECD(+) 310-OR(+)670-flavanone for the first and second eluted peaks, respectively. Calculation of the ECD spectrum of one enantiomer at the TD-DFT/DGTZVP level of theory yielded the (S)-ECD(-)310-OR(-)670 and (R)-ECD(+)310-OR(+)670-1 absolute configuration, in agreement with the use of empirical rules for stereochemical assignment. Vibrational circular dichroism spectra of enantiopure compounds, obtained through fraction collection during repeated HPLC runs, were recorded and compared with theoretical traces produced from DFT calculations at the B3LYP/DGDZVP and B3PW91/DGDZVP levels of theory, which further confirmed the absolute configuration obtained from the on-line chiroptical data.
手性高效液相色谱联用电子圆二色光谱和激光旋光检测（HPLC-ECD-OR）首次实现了外消旋黄烷酮（1）两种对映体的在线手性光学表征，分别对应于第一个和第二个洗脱峰的ECD（-）310-OR（-）670-黄烷酮和ECD（+）310-OR（+）670-黄烷酮。在TD-DFT/DGTZVP理论水平上计算一种对映体的ECD光谱，得到（S）-ECD（-）310-OR（-）670和（R）-ECD（+）310-OR（+）670-1的绝对构型，这与使用立体化学归属的经验规则一致。通过在重复的HPLC运行过程中进行馏分收集获得对映体纯化合物的振动圆二色光谱，并与在B3LYP/DGDZVP和B3PW91/DGDZVP理论水平上由DFT计算产生的理论谱线进行比较，这进一步证实了从在线手性光学数据获得的绝对构型。
