outcome of the reaction is reversed from no reaction to almost quantitative yield of the expected product simply by switching the order of the addition of the reagents to the presumed acyloxyphosphonium intermediate. If triethylamine was present before treatment with 1H-benzotriazole, anhydride was always exclusively generated without a detectable amount of the expected product. However, if the base
在尝试通过使用 Ph3P/I2 作为酸活化系统将
羧酸直接转化为 N-酰基苯并三唑时,反应的结果从没有反应逆转为几乎定量的预期产物产率,只需改变加入的顺序即可假定的酰氧基
磷中间体的试剂。如果在用 1H-苯并三唑处理之前存在
三乙胺,则总是仅生成酸酐而没有可检测量的预期产物。然而,如果在加入 1H-苯并三唑后使用碱,则反应顺利进行,在较短的反应时间内以良好至极好的产率得到 N-酰基苯并三唑。