Amphiphilic pyrimidinophane, a new dimeric surfactant: Synthesis, aggregation, and catalytic activity

摘要

Tensiometry, conductometry, dynamic light scattering, and potentiometry are used to study the aggregation of a new amphiphilic alkylated pyrimidinophane (APP) in aqueous solutions in the presence of polyethylenimine. The new geminal surfactant is shown to possess high micellization ability (CMC = 0.00001M) due to the presence of an additional alkyl radical in the pyrimidine fragment. APP aggregates are characterized by a low degree of counterion binding (lower than 50%). Spectrophotometry is employed to investigate the catalytic activities of individual surfactant solutions and solutions of APP-polyethylenimine binary mixtures with respect to the hydrolysis of phosphonic acid esters. The effect of APP on phosphonate hydrolysis is typical of cationic surfactants. The higher acceleration is observed for the hydrolysis of a more hydrophobic phophonate.