首页 | 本学科首页   官方微博 | 高级检索  
     检索      

光诱导呫吨酮电子转移和氢转移反应的激光闪光光解研究
引用本文:王金婷,潘洋,张立敏,俞书勤.光诱导呫吨酮电子转移和氢转移反应的激光闪光光解研究[J].化学物理学报,2007,20(4):395-400.
作者姓名:王金婷  潘洋  张立敏  俞书勤
作者单位:中国科学技术大学化学物理系,合肥230026,中国科学技术大学化学物理系,合肥230026,中国科学技术大学化学物理系,合肥230026,中国科学技术大学化学物理系,合肥230026
摘    要:用时间分辨激光闪光光解的方法研究了在乙腈溶剂中呫吨酮的激发三重态的性质,并得到了呫吨酮激发三重态和胺类、醇类以及酚类反应的瞬态吸收光谱和猝灭速率常数(kq).除了苯胺和3-硝基苯胺被认为是能量转移外,呫吨酮和其余胺类的反应随着自由能变的减校lgkq逐渐增大,由此认为发生了电子转移反应.而对于二甲基-对甲苯胺、3,5,N,N-四甲基苯胺、N,N-二甲基苯胺、三乙胺来说,通过瞬态吸收光谱的变化可以知道既有电子转移反应又有氢转移反应发生.呫吨酮和醇类只发生氢转移反应,其猝灭速率常数和醇的?-C?H的键能有关.由

关 键 词:激光闪光光解    呫吨酮    电子转移    氢转移
收稿时间:2007/5/14 0:00:00
修稿时间:2007/5/20 0:00:00

Photoinduced Electron and H-atom Transfer Reactions of Xanthone by Laser Flash Photolysis
Jin-ting Wang,Yang Pan,Li-min Zhang and Shu-qin Yu.Photoinduced Electron and H-atom Transfer Reactions of Xanthone by Laser Flash Photolysis[J].Chinese Journal of Chemical Physics,2007,20(4):395-400.
Authors:Jin-ting Wang  Yang Pan  Li-min Zhang and Shu-qin Yu
Institution:Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China,Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China,Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China,Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
Abstract:The property of the lowest excited triplet states of xanthone in acetonitrile was investigated using time-resolved laser °ash photolysis at 355 nm. The transient absorption spectra and the quenching rate constants(kq) of the excited xanthone with several amines were determined. Good correlation between lgkq and the driving force of the reactions suggests the electron transfer mechanism, except aniline and 3-nitroaniline (3-NO2-A) which showed energy transfer mechanism. With the appearance of ketyl radical, hydrogen atom transfer also happened between xanthone and dimethyl-p-toluidine, 3,5,N,N-tetramethylaniline, N,N-dimethylaniline, and triethylamine. Therefore, both electron transfer and H-atom transfer occured in these systems. Great discrepancies of kq values were discovered in H-atom abstraction reactions for alcohols and phenols, which can be explained by di?erent abstraction mechanisms. The quenching rate constants between xanthone and alcohols correlate well with the ?-C?H bonding energy of alcohols.
Keywords:
点击此处可从《化学物理学报》浏览原始摘要信息
点击此处可从《化学物理学报》下载免费的PDF全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号