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The kinetics of hydrolysis of bis (p-nitrophenyl] methylphosphonate in the presence of prima/3' aliphatic amines in aqueous micellar solutions of cetylpyridinium bromide was studied. Tile reaction proceeds via tv, o routes, alkaline hydrolysis and amine-catalyzed hydrolysis according to the general basic catalysis mechanism. The contributions of these routes and the catalytic effect of mieelles depend on the hydrophobicity of the amines. The formation of different types of miceltes was found, and their characteristic parameters were determined by tensiometr7 and high-resolution t H N M R spectroscopy with a magnetic field pulse gradient.Key words: kinetics, hydrolysis, bistp-nitrophenyl) methylphosphonate, amines, micetles. cetytpyridinium bromide. ~|t NMR spectroscopy, diffusion.Micellar catalysis is a nontraditional method of affecting the reactivity of org~mic compounds.l'2 Elucidation of the factors that determine the efficiency of micellar catalysis is a topical task. The line of investigation of micelle formation and micellar catalysis is tightly connected with the problems of enzymology, because most processes involving enzymes cxzcur in highly organized systems, namely, cell membranes and subceflular species. Micellar solutions can ser~'e as convenient models for the investigation of it/ vitro processes occurring in a living cell) Functionalization of micelles of cationic suffactants by incorporation of long-chain amines (i.e., the /brmation of mixed aggregates bearing a fixed active site responding to the variation of the medium pH and the component ratio) can result in the design of biomimetic systems. These systems exhibit catalytic activity in nucleophilic cleavage processes, in particular, in the transfer of acyl and phospho~t groups.This work is a continuation of our study dealing with the catalytic properties of micellar systems consisting of a surfactant and a primary' aliphatic amine. 4,5 It is aimed at elucidating the relationship between the structures of microaggregates and their influence on the rate and mechanism of cleavage of ester bonds. For this purpose. using bis(ao-nitrophenyt) methylphosphonate (1) as the sttbstrate, we studied the kinetics of hydrolysis of esters of tetracoordinated phosphorus in the presence of primar7 amines with nonbranched chains in aqueous micellar solutions of cetylpyridinium bromide (CPB). A number of characteristic parameters of the system confirming the fomaation of micellar aggregates of various types were determined by independent physical methods (tensiometry" and high-resolution ~H NMR spectroscopy with a magnetic field pulse gradient). ExperimentalThe solvents and amines were purified by standard procedures. CPB samples were twice reprecipitated with ether from ethanol. Phosphonatc 1 was synthesized and purified by a procedure reported previously. 6The formation of tile O-(p-nitrophenyl) methylphosphonic acid monoanion upon hydrolysis of compound 1 in solutions of CPB in the presence of decylamine is proved by the fact that its chemical shift in the 3t...