Synthesis and Catalytic Activity of Surfactant Analogues of 4- (Dimethylamino) pyridine

Seven surfactants have been synthesized, each containing a 4-(dialkylamino)pyridine moiety carrying an 8-10-carbon chain with an attached polar or charged group. Two of the compounds fall into the neutral charge category, two are cationic, two are zwitterionic, and one is anionic. Rates of hydrolysis of 4-nitrophenyl hexanoate and 1,2,2-trimethylpropyl methylphosphonofluoridate by each surfactant were measured, both with and without added cetyltrimethylammonium chloride (CTAC). The most active derivative, sodium 10- [butyl(4-pyridinyl)amino]decyl sulfate (12), catalyzed the hydrolysis of 4-nitrophenyl hexanoate with k2 = 38.0 M-' s-l at pH 8.5, which compares favorably to the catalysis by o-iodosobenzoate derivatives investigated by Moss and co-workers. The present catalysts, in contrast to the iodosobenzoates, show poor rate enhancements in the hydrolysis of fluorophosphonates.