Synthesis and ion-binding affinities of calix[4]arenes immobilized on cross-linked polystyrene

Calix[4]arene and its diphosphorylated derivative have been immobilized ont o cross-linked polystyrene beads through an etherification reaction. The su pported calixarene complexes 96.7% Cs(I) from a 10(-4) N solution in 1 M Na OH. Poly(hydroxystyrene) complexes 35.6% Cs(I) from the same solution. Immo bilization of the calixarene onto a polymer support thus does not affect it s inherently high affinity for cesium ions. Substituting two of the three r emaining hydroxyl groups on the calixarene with diethoxyphosphoryl moieties allows for quantitative complexation of Fe(III) and Pb(II) from 0.01 M nit ric acid solutions. The unsubstituted calixarene complexes 6.00% Fe(III) an d 7.36% Pb(II) while diethoxy-phosphoryl-substituted poly(hydroxystyrene) c omplexes 10.0% Fe(III) and 3.76%, Pb(II). The calixarene therefore acts as a platform on which ligands can be immobilized in close enough proximity to permit cooperative binding of metal ions.