Wainer I W, Alembik M C
J Chromatogr. 1986 May 16;358(1):85-93. doi: 10.1016/s0021-9673(01)90318-8.
A series of enantiomeric amides were resolved on a commercially available chiral stationary phase (CSP) consisting of cellulose tribenzoate coated on macroporous silica. The amides were synthesized from several homologous series of aliphatic and aromatic chiral amines and a series of aliphatic chiral acids. The results of the study indicate that the formation of the solute-CSP diastereomeric complex is based on a combination of hydrogen bonding, pi-pi and amide dipole interactions. These interactions not only form the diastereomeric complex but also appear to position the solute and CSP within the complex. This is suggested by the fact that the enantiomeric elution order for a series of amides formed from aliphatic amines is R, S, whereas the enantiomeric elution order for the corresponding series of amides formed from aliphatic acids is S, R. The effects of steric bulk at the chiral center were also investigated; the results indicate that for the homologous series of aliphatic amides, an increase in the length of the alkyl chain attached to the chiral center results in an increase in the chiral resolution (alpha). This is not the case, however, for the homologous series of aromatic amides; the results suggest that chiral recognition is a function of the fit of the asymmetric portion of the solute in a chiral cavity (or channel) of the CSP and that this fit has rigid steric requirements.
一系列对映体酰胺在一种市售的手性固定相（CSP）上进行拆分，该固定相由涂覆在大孔硅胶上的三苯甲酸纤维素组成。这些酰胺由几个同系的脂肪族和芳香族手性胺以及一系列脂肪族手性酸合成。研究结果表明，溶质 - CSP非对映体复合物的形成基于氢键、π - π和酰胺偶极相互作用的组合。这些相互作用不仅形成非对映体复合物，而且似乎还在复合物中定位溶质和CSP。这一点由以下事实表明：由脂肪族胺形成的一系列酰胺的对映体洗脱顺序为R、S，而由脂肪族酸形成的相应系列酰胺的对映体洗脱顺序为S、R。还研究了手性中心处空间位阻的影响；结果表明，对于脂肪族酰胺的同系物系列，连接到手性中心的烷基链长度增加会导致手性拆分度（α）增加。然而，对于芳香族酰胺的同系物系列情况并非如此；结果表明，手性识别是溶质不对称部分在手性固定相的手性腔（或通道）中的适配函数，并且这种适配具有严格的空间要求。
