Novel sucrose-based macrocyclic receptors for enantioselective recognition of chiral ammonium cations
摘要:
A new synthetic route to macrocyclic sucrose-based receptors with different substituents at the ring nitrogen atom is described. Very good enantioselectivity toward phenylethylammonium chloride was observed [a much stronger complex with the cation of the (S)-amine was formed] although the K-a values were low. Much higher K-a (1.4 x 10(4) M-1 in CDCI3/CD3OD) values of the complexes with aminoacid derivatives (especially valine) were found although this time the enantioselectivities were moderate. (C) 2012 Elsevier Ltd. All rights reserved.