COORDINATION PROPERTIES OF 6-DEOXY-6-[1-(2-AMINO) ETHYLAMINO]-BETA-CYCLODEXTRIN AND THE ABILITY OF ITS COPPER(II) COMPLEX TO RECOGNIZE AND SEPARATE AMINO-ACID ENANTIOMERIC PAIRS
Rp. Bonomo et al., COORDINATION PROPERTIES OF 6-DEOXY-6-[1-(2-AMINO) ETHYLAMINO]-BETA-CYCLODEXTRIN AND THE ABILITY OF ITS COPPER(II) COMPLEX TO RECOGNIZE AND SEPARATE AMINO-ACID ENANTIOMERIC PAIRS, Journal of inclusion phenomena and molecular recognition in chemistry, 15(2), 1993, pp. 167-180
The functionalized cyclodextrin -deoxy-6-[1-(2-amino)ethylamino]-beta-
cyclodextrin was synthesized, and an NMR, EPR, pH-metric, and calorime
tric investigation was carried out in aqueous solution in order to asc
ertain its behaviour towards protonation and copper(II) complex format
ion. The thermodynamic parameters of the ternary complex formation wit
h alanine, phenylalanine and tryptophan enantiomeric pairs were also d
etermined (25-degrees-C and I = 0.1 mol dm- 3). No thermodynamic enant
ioselectivity was observed in these systems, while a chiral, though po
or, discrimination was observed in LEC: c.d. spectra also show enantio
meric stereoselectivity. The results of the present investigation, com
pared with previously reported results, suggest the occurrence of a ci
s-complex reversible trans-complex equilibrium in such systems.