NMR and Spectrophotometry Study of the Supramolecular Catalytic System Based on Polyethyleneimine and Amphiphilic Sulfonatomethylated Calix[4]Resorcinarene

The aggregation behavior and catalytic activity of the polyethyleneimine (PEI) and sulfonatomethylated calix[4]resorcinarene (SCA) based systems are studied by methods of the NMR and UV−vis spectroscopy. The investigation of the kinetics of hydrolysis of the p-nitrophenyl dimethyl phosphate revealed two reaction routes in both the single PEI solution and the binary PEI-SCA system. Although SCA alone shows no catalytic activity, a 10-fold synergetic catalytic effect is achieved in the binary PEI-SCA system as compared to the single PEI systems at the SCA concentrations below the critical micelle concentration (cmc) of 0.011 M originating from the tensiometry data. The inclusive type of interactions involving the calixarene cavity is shown to contribute to the PEI-SCA self-assembly in the concentration range below this cmc value, which is probably responsible for the above rate acceleration. The different modes of self-organization assuming the PEI inclusion into the calixarene cavity are discussed.