Good chiral recognition of diketopiperazines has been obtained with a receptor that combines a xanthone with a phosphonamide as an asymmetric group. Silicagel plates impregnated with an enantiomerically pure diketopiperazine provide an easy and effective way to resolve the receptor racemic mixture. The strong (R,R. R) complex yields a spot with a larger Rf, probably because the complex is less polar than the free receptor.
利用一种将
黄酮与膦酰胺作为不对称基团结合在一起的受体,可以很好地识别二酮
哌嗪的手性。浸渍了对映体纯的二酮
哌嗪的
硅胶板提供了一种简单有效的方法来分辨受体的外消旋混合物。强(R,R. R)络合物产生的光斑 Rf 较大,这可能是因为络合物的极性小于游离受体。