Effect of beta-cyclodextrin acetylation on the resolution of phenethylamines with capillary electrophoresis and nuclear magnetic resonance spectroscopy

The effect of acetylation of beta-cyclodextrin (CD) on the chiral discrimination of a series of phenethylamines has been investigated using capillary electrophoresis and nuclear magnetic resonance (NMR) spectroscopy, Therefore, pure, fully derivatized CDs were synthesized. Capillary electrophoresis measurements revealed that the 2,3-diacetylated CD was a better discriminator than the 6-acetylated and the native CD. NMR investigations of the complexes suggest that the phenyl ring of the phenethylamines is inserted in the cavity and the side chair. interacts with the hydroxyl rim of the macrocycle. The structures of the complexes indicated by the NMR results were supported by molecular models of the derivatised CDs.