No abstract

we should take into account not only their hydrophobic properties but also the efficiency of substrate solubilization as well as the reactivity of the oximate group in the surfactant micelles.The unflagging interest during recent decades in the synthesis and reactivity of surfactants with nucleophilic functional groups is a consequence of a number of factors. Firstly, microheterogeneous systems derived from functional detergents serve, to some extent, as models for studying the action of hydrolytic enzymes, which provides for the investigation of various features of enzymatic catalysis in simpler systems. The increase in the reaction rate in micelles of functional surfactants in comparison with water may reach factors of 10 2 -10 7 , which makes such systems comparable in efficiency with enzyme systems [1,2]. The observed effects are largely a function of the role of the microenvironment of that part of the micelles, in which the chemical reaction proceeds and the hydrophobic binding of the substrate by the micelle core [1][2][3][4]. Secondly, the intensive study of the reactivity of functional detergents has had and still has marked applied significance related to the decomposition and utilization of environmental toxicants, in particular the highly toxic esters of organophosphorus acids [1,[5][6][7][8].Modification of functional surfactants in order to obtain highly efficient supernucleophilic systems requires us to establish the factors responsible for the micelle effects of detergents. In previous work [9], we showed that, in the case of surfactants with an oximate group, nucleophilicity is directly related to the acid-base properties of the oximate group. In this instance, as in the case of oximes, which do not form micelles, the Brönsted catalysis equation is not linear and has an inflection point at pK a » 8.5-9.0 [9, 10]. Since the concentration of the substrate in the micellar pseudophase makes the major contribution to the increase in the observed reaction rate [10], the hydrophobic properties of the functional surfactants have fundamental importance in the manifestation of their micellar effects [1,[11][12][13].

No abstract

No abstract

No abstract