Deepened chiral cavitands

Deep cavitands bearing eight asymmetric centers on their upper rims are prepared from octamino resorcinarenes. The resorcinarenes are acylated with Fmoc d- and l-alanine or Fmoc glycine acid chlorides. The asymmetric centers create a chiral magnetic environment as shown by binding achiral ɛ-caprolactam. The chiral steric environment shows modest enantioselectivity (55% de) for chiral guests such as pinane diols bound inside the cavitand.

Graphical abstractThe synthesis and binding properties in solution of a new family of deep, chiral cavitands are described. The directionality of the hydrogen bond array on cavitand's upper rim is controlled by the presence of appropriately positioned asymmetric centers, creating a chiral hydrophobic pocket.Download full-size image