Synthesis, Enantiomer Separation, and Absolute Configuration of 2,6-Oxygenated 9-Azabicyclo[3.3.1]nonanes
作者:Vidmantas Bieliu̅nas、Dovilė Račkauskaitė、Edvinas Orentas、Sigitas Stončius
DOI:10.1021/jo400506h
日期:2013.6.7
converted into the corresponding enantiomerically pure diones 4b, the absolute configuration of which was determined by comparison of the experimental and simulated circular dichroism (CD) spectra, obtained by ab initio time-dependent density functional theory (TDDFT) calculations. The (−)-(1R,5R)/(+)-(1S,5S) absolute configuration of 4b inferred from the TDDFT calculations was confirmed via analysis
对映体纯的N -Boc 9-氮杂双环[3.3.1]壬烷-2,6-二酮(4b)是一种可能有用的手性结构单元,由N -Bn和N -Boc 9-氮杂双环[3.3.1]合成。完成了壬壬-2,6-二醇2a和2b。二醇2a和2b的对映异构体拆分是通过使它们的非对映体酯结晶或使用来自假丝酵母(CRL)的脂肪酶通过动力学拆分外消旋二醇2a而实现的。N- Boc保护的二醇2b的两种对映体均转化为相应的对映体纯二酮参照图4b,其绝对构型是通过比较实验和模拟圆二色性(CD)光谱确定的,该光谱是通过从头算时密度函数理论(TDDFT)计算获得的。根据对TDDFT计算的推论,通过对内,内二苯甲酸内酯(+)的CD谱的分析证实了4b的(-)-(1 R,5 R)/(+)-(1 S,5 S)绝对构型-由二醇(+)2b衍生的-7和苯甲酸酯激子手性方法的应用。二醇2a的动力学拆分结果进一步支持了分配的绝对构型使用皱纹念珠菌脂肪酶,其对(1