In order to analyze the selectivity of the oxidizing agent on the chemical oxidation of pindolol in methanol/acidic media, the reaction of pindolol by peroxodiphosphate [PDP] in acidic media was studied. It was found that the reaction mechanism is comparable with other peroxides, however, reaction products are different depending on the acidity condition, at low acid concentration, oxipindolol is formed through acid catalyzed transformation of the indonlonic intermediate while at high acid concentration, the intermediate can react through competing parallel reaction to produce three products (oxipindolol, dioxipindolol and indigo form of pindolol) for the 1-PDP reaction. It is also found that, under present experimental conditions, neutral H4P2O8 is the active species involved in the oxidation process. Comparison of kinetics behaviour of the 1-PDP reaction with other peroxides were also investigated and we conclude that H4P2O8 is more reactive than H2S2O8 while HS2O8– is better electrophilic compared to the H3P2O8–.
为了分析氧化剂在
甲醇/酸性介质中对
吲哚洛尔化学氧化的选择性,研究了过二
磷酸[PDP]在酸性介质中对
吲哚洛尔的反应。研究发现,反应机理与其他过氧化物相似,但反应产物随酸度条件的不同而不同,在低酸浓度下,通过酸催化
吲哚酮中间体的转化生成
肟吲哚洛尔,而在高酸浓度下,该中间体可通过竞争并联反应生成 1-PDP 反应的三种产物(
肟吲哚洛尔、二氧
嘧啶洛尔和靛蓝形式的
吲哚洛尔)。研究还发现,在目前的实验条件下,中性 H4P2O8 是参与氧化过程的活性物种。我们还对 1-PDP 反应与其他过氧化物的动力学行为进行了比较,得出的结论是 H4P2O8 H4P2O8 比 H2S2O8 反应性更强,而 HS2O8– 与 H3P2O8– 相比亲电性更好。