Hybrid materials comprising trimethylglycinamide groups: immobilization consequences for anion binding affinities

A thorough binding study of three trimethylglycinamide functionalized mesoporous silica gels is reported. Anion-exchange properties of these hybrid materials were established alongside the properties of their organic analogues, to provide insight into the effects of ligand immobilization on the selectivity and effectiveness of anion binding. Chloride, benzoate, nitrate, oxalate, dichromate and phosphate salts were examined. Materials and compounds after the ion exchange were studied by potentiometric titration, FTIR and 1H NMR spectroscopy. The data acquired indicate that immobilization is a viable alternative to high preorganization of a successful host molecule.