A new method to study antioxidant capability:: Hydrogen transfer from phenols to a prefluorescent nitroxide
A new method to study antioxidant capability:: Hydrogen transfer from phenols to a prefluorescent nitroxide
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DOI：
10.1021/ol035589w
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发表时间：
2003-10-30
期刊：
影响因子：
5.2
通讯作者：
Scaiano, JC
中科院分区：
文献类型：
--
作者：
Aliaga, C;Aspée, A;Scaiano, JC
[摘要]报道了用前荧光-TEMPO探针从酚类中提取氢的速率常数。氮氧自由基被用作过氧自由基的潜在模型。该探针通过氮氧抑制发色团的荧光来工作。当氮氧化合物夺取一个氢原子产生抗磁性羟胺时，荧光恢复。在这个项目中研究的酚表现出的速率常数在0.003和0.2 M-1 s（-1）之间。TROLOX的氘同位素效应为10，证实了该机制是由氢转移主导的。
[ABSTRACT]Rate constants for hydrogen abstraction from phenols by a prefluorescent-TEMPO probe are reported. The nitroxide is employed as a potential model of peroxyl radicals. The probe works by nitroxide suppression of the fluorescence of the chromophore. The fluorescence is restored when the nitroxide abstracts a hydrogen atom to produce the diamagnetic hydroxylamine. The phenols studied in this project exhibited rate constants between 0.003 and 0.2 M-1 s(-1). A deuterium isotope effect of 10 for TROLOX confirms that the mechanism is dominated by hydrogen transfer.