Mechanism of oxygenation of aryl methyl and diaryl sulphoxides by peroxomonophosphoric acid
作者:R. Suthakaran、S. Rajagopal、C. Srinivasan
DOI:10.1016/s0040-4020(00)01105-4
日期:2001.2
the title sulphoxides by peroxomonophosphoric acid in aqueous acetic acid follows an overall second-order kinetics, first-order in each reactant. An analysis of the influence of [H+] reveals that H3PO5 is the active species in the oxidation. The structure–reactivity studies with different substituents on the phenyl ring give evidence for the formation of an electron deficient sulphonium ion intermediate
乙酸水溶液中过氧一磷酸对标题亚砜的氧化动力学遵循总体二级动力学,即每个反应物中的一级动力学。对[H + ]影响的分析表明,H 3 PO 5是氧化中的活性物质。苯环上具有不同取代基的结构反应性研究提供了形成缺电子sulph离子中间体的证据,因为log k 2和σ之间的相关性 给出了一个负ρ值(ρ = -0.47±0.09,r = 0.988,小号= 0.03在35℃下为芳基甲基亚砜和ρ对于二芳基亚砜在35°C时= -0.54±0.11,r = 0.983,s = 0.07)。提出该机理涉及在限速步骤中亚砜硫对H 3 PO 5的过氧-氧的亲核攻击。