Surfactant Research Chair, Department of Chemistry, College of Science, King Saud University, Riyadh 11541, Saudi Arabia.
J Colloid Interface Sci. 2011 May 15;357(2):393-9. doi: 10.1016/j.jcis.2011.02.004.
Herein we have investigated the hydrolysis of 1H-indol-2,3-dione (isatin, I) and its derivatives of different hydrophobicities, viz. N-dimethylaminomethyl indol-2,3-dione (II), N-morpholinomethyl indol-2,3-dione (III), N-pipridinomethyl indol-2,3-dione (IV), N-heptylaminomethyl indol-2,3-dione (V), N-dodecylaminomethyl indol-2,3-dione (VI), N-hexylanilinomethyl indol-2,3-dione (VII), N-decylanilinomethyl indol-2,3-dione (VIII), and N-hexadecylanilinomethyl indol-2,3-dione (IX), in the presence of an excess amount of sodium hydroxide. All the isatin derivatives were synthesized in the laboratory. The progress of the reactions was studied by exploiting UV-visible spectrophotometry. The observed rate constant, k(w), increases linearly on increasing the hydroxide ion concentration, indicating first-order dependence on [OH(-)]. The effects of surfactants, cationic (cetyltrimethylammonium chloride, CTACl), and anionic (sodium dodecyl sulfate, SDS) were also investigated. The rate of reaction increased on increasing the concentration of CTACl and, after reaching a maximum, it started decreasing. Conversely, anionic micelles of SDS inhibited the rate of hydrolysis of isatin and its derivatives. The results of the effect of CTACl were analyzed using a pseudophase ion-exchange model while the inhibition by SDS was analyzed using a simple Menger-Portnoy model. The effects of added salts, such as NaBr, NaCl, and (CH(3))(4)NBr, were also seen on the isatin hydrolysis. It was found that the addition of salts decreased the rate enhancement efficiency of the CTACl.
在此，我们研究了 1H-吲哚-2,3-二酮（靛红，I）及其不同疏水性衍生物的水解，例如 N-二甲基氨甲基吲哚-2,3-二酮（II）、N-吗啉甲基吲哚-2,3-二酮（III）、N-哌啶甲基吲哚-2,3-二酮（IV）、N-正庚基氨甲基吲哚-2,3-二酮（V）、N-十二烷基氨甲基吲哚-2,3-二酮（VI）、N-正己基苯胺甲基吲哚-2,3-二酮（VII）、N-正癸基苯胺甲基吲哚-2,3-二酮（VIII）和 N-十六烷基苯胺甲基吲哚-2,3-二酮（IX），在过量氢氧化钠存在下。所有的靛红衍生物都是在实验室合成的。通过紫外可见分光光度法研究了反应的进展。观察到的速率常数 k(w)随氢氧根离子浓度的增加呈线性增加，表明对[OH(-)]呈一级依赖关系。还研究了表面活性剂阳离子（十六烷基三甲基氯化铵，CTACl）和阴离子（十二烷基硫酸钠，SDS）的影响。随着 CTACl 浓度的增加，反应速率增加，达到最大值后开始降低。相反，SDS 的阴离子胶束抑制了靛红及其衍生物的水解速率。用拟相间离子交换模型分析了 CTACl 的影响，而用简单的 Menger-Portnoy 模型分析了 SDS 的抑制作用。还观察到添加盐（如 NaBr、NaCl 和（CH(3))(4)NBr）对靛红水解的影响。发现添加盐降低了 CTACl 的速率增强效率。
