The HOOSO3- oxidation of eleven meta- and para-substituted anilines to the corresponding nitrosobenzenes at pH ≈ 11 was characterized by the rate equation v = kK[OX][An]/(1 + K[An]). Formation constant of the reactive intermediate and its rate of decomposition were evaluated separately for ascertaining the structure-reactivity relationships. Under the experimental conditions the dianion, -O-O-SO3- is probably the effective electrophile. Kinetic data can be rationalized by a bimolecular process which involves the attack of nucleophilic nitrogen atom on the peroxidic oxygen. The highlight of the study is the opposite curvatures observed in the nonlinear Hammett plots of first-order rate constant k and the "equilibrium" constant K, being concave downward and upward, respectively.
HOOSO3-氧化十一个取代苯胺的对位和间位取代物,生成相应的亚硝基苯在pH≈11的速率方程式v = kK[OX][An]/(1 + K[An])。通过评估反应中间体的形成常数及其分解速率,确定了结构-反应性关系。在实验条件下,二阴离子O-O-SO3-可能是有效的亲电试剂。动力学数据可以通过一个双分子过程来解释,其中亲核氮原子攻击过氧氧原子。研究的亮点是观察到的一阶速率常数k和“平衡”常数K的非线性Hammett图的相反曲率,分别为向下凹和向上凸。