Mechanism of the 10-methylacridinium ion-sensitized photooxidation of N,N-dibenzylhydroxylamine and its derivatives in acetonitrile
作者:Yasuhiro Ohba、Kanji Kubo、Tetsutaro Igarashi、Tadamitsu Sakurai
DOI:10.1039/b009206l
日期:——
The 10-methylacridinium ion (MA+)-sensitized photooxidation
of substituted N,N-dibenzylhydroxylamines (1) in acetonitrile occurred mainly by a superoxide
ion mechanism to give N-benzylidenebenzylamine N-oxides
(2) and hydrogen peroxide quantitatively.
Analysis of substituent effects on the limiting quantum yield for formation
of 2 showed that back electron transfer
(ET) from the 10-methylacridinyl radical (MA˙) to the radical cation 1+˙ proceeds in the Marcus ‘normal
region’. In addition, this back ET was found to take place in preference
to one-electron reduction of O2 by MA˙.
取代的 N,N-二苄基羟胺(1)在乙腈中的 10-甲基吖啶离子(MA+)敏化光氧化反应主要是通过超氧离子机制发生的,从而定量生成 N-亚苄基苄胺 N-氧化物(2)和过氧化氢。
分析取代基对生成 2 的极限量子产率的影响表明,从 10-甲基吖啶基(MA˙)到自由基阳离子 1+˙ 的反向电子转移(ET)是在马库斯 "正常区域 "进行的。此外,还发现这种反向 ET 比 MA˙对 O2 的单电子还原更优先发生。