| Abstract |
The metal cation binding ability of cone-p-tert-butylhexahomotrioxacalix[3]arene tris(acetic acid) was investigated by H-1 NMR and complementary semi-empirical calculations. NMR showed significant shifts with Na+, K+, Ag+ and, to a lesser extent, Pb2+. The macrocyclic protons undergoing the greatest shifts imply that these cations bind inside the cavity composed of the phenoxy and carbonyl oxygen atoms. Metal complexes were modelled using a semi-empirical approach and, in general, their geometry optimised structures were in agreement with NMR data. U-tube transport experiments demonstrated that the macrocycle actively transported Cr3+, Fe3+, Co2+ and Cu2+ through the organic phase. |
