Calix[4]arenes with proton-ionizable groups on the lower and upper rim

In this thesis research, calix[4]arene ligands with proton-ionizable groups on the lower and upper rim have been prepared using calix[4]arene as the scaffold. Two major projects have been successfully accomplished. In the first, di-ionizable calix[4]arene ligands and p-tert-butylcalix[4]arene ligands with proton-ionizable groups on the lower rim were synthesized. The objective is to investigate the effect of benzyl substitution on the lower rim with p-tert-butyl substitution on the upper rim on their metal ion complexation abilities, which will provide information concerning how benzyl- and para-substituents affect extraction efficiency and selectivity. In the second project, three series of di-ionizable calix[4]arene ligands with proton-ionizable groups on the upper rim were synthesized. p-Carboxycalix[4]arene ligands and p-carboxymethylcalix[4]arene ligands have two proton-ionizable N-(X)sulfonyl carboxamide groups on the upper rim and four methoxy groups on the lower rim. p-Carboxycalix[4]arene-crown-5 ligands have two N-(X)sulfonyl carboxamide groups on the upper rim and a crown-5 ring on the lower rim. The main objective of second project is to evaluate effect of proton-ionizble groups on the upper rim with a crown ether unit on the lower rim on their metal ions complexation abilities.