作者:Chockalingam Karunakaran、Ramasamy Kamalam
DOI:10.1039/b208199g
日期:2002.12.6
Perborate but not percarbonate in acetic acid generates peracetic acid on standing and the peracetic acid oxidation of anilines is fast. The oxidation with a fresh solution of perborate in acetic acid is smooth and second order but the specific oxidation rate increases with increasing [perborate]0 or [boric acid]. Perborate on dissolution affords hydrogen peroxide and a borate; the latter assists the former in the oxidation. The oxidation rates of anilines under identical conditions do not conform to any of the linear free energy relationships but the reaction rates of molecular anilines do. Perborate oxidation proceeds via two reaction paths but the overall oxidation rates of molecular anilines conform to structure–reactivity relationships; the transition states do not differ significantly. Analysis of the oxidation rates of perborate and percarbonate reveals that while perborate oxidation is faster than percarbonate it is at least as selective as the latter.
在乙酸中,过硼酸盐而非过碳酸盐静置时会产生过乙酸,而过乙酸对苯胺的氧化反应迅速。使用新鲜配制的乙酸过硼酸盐溶液进行氧化反应平稳且具有二级反应特性,但特定的氧化速率随[过硼酸盐]0或[硼酸]浓度的增加而增加。过硼酸盐溶解时产生过氧化氢和硼酸盐;后者在氧化过程中辅助前者。在相同条件下,苯胺的氧化速率不符合任何线性自由能关系,但分子苯胺的反应速率却符合。过硼酸盐氧化通过两条反应路径进行,但分子苯胺的整体氧化速率符合结构-反应活性关系;过渡态的差异不大。对过硼酸盐和过碳酸盐氧化速率的分析显示,尽管过硼酸盐的氧化速率更快,但其选择性至少不亚于过碳酸盐。