Reactivity of inorganic α-nucleophiles in acyl group transfer processes in water and surfactant micelles: I. Systems based on organic complexes of tribromide anion
作者:M. K. Turovskaya、V. A. Mikhailov、N. I. Burakov、I. V. Kapitanov、T. M. Zubareva、V. L. Lobachev、B. V. Panchenko、T. M. Prokop’eva
DOI:10.1134/s107042801703006x
日期:2017.3
from water to micelles. Micellar effects of surfactants are determined by the nucleophilicity of hypobromite ion in surfactant micelles and by solubilization of the substrate and BrO–, which largely depend on the counterion concentration in the micelle surface layer. The main factor responsible for the observed acceleration is increased reactant concentration in the micellar pseudophase.
基于三溴阴离子有机配合物的系统在溶解于亲核氧化剂对HOBr / BrO中后生成,并且将4-硝基苯基乙基膦酸乙酯,4-硝基苯基磷酸二乙酯和4-硝基苯基对甲苯磺酸酯的水解速度提高了15– 90在阳离子表面活性剂胶束的存在下。与在水中一样,表面活性剂胶束中的次溴酸盐离子充当α-亲核试剂,从水到胶束时,α效应的大小几乎不变。表面活性剂的胶束效应取决于表面活性剂胶束中次溴酸盐离子的亲核性以及底物和BrO的增溶作用–,这主要取决于胶束表面层中的抗衡离子浓度。引起观察到的加速的主要因素是胶束假相中反应物浓度的增加。