2-苯基吲哚单重态氧反应机理

Mechanism of Singlet Oxygenation of 2-Phenylindole

本文比较了在甲醇介质下,2-苯基吲哚(1)单重态氧反应中的捕捉反应以及2-苯基-3H-吲哚-3-酮(4)的亲核加成反应特征。结果显示,在1的单重态氧反应中.捕捉反应主要发生于两性离子(2)阶段,而4并非导致捕捉产物的重要中间体。根据上述事实,结合有关反应溶剂极性效应的研究结果,对反应机理进行了探讨。

Trapping reactions in singlet oxygenation of 2-phenylindole (1) and nucleophilic addition reactions of 2-phenyl-3H-indol-3-one (4) both in methanolic media were studied comparatively. It was showed that trapping reactions in singlet oxygenation of 1 occured mainly on the stage of zwitterionic intermediate (2), whereas 4 was not a major precursor to trapping products. In views of such a conclusion as well as the observations on solvent polarity effect of the singlet oxygen reaction, a possible mechanism was proposed.