Rate coefficients for the reactions of cyclohexadienyl (c-C6H7) radicals with O2 and NO at room temperature
摘要:
Rate coefficients for the reactions of cyclohexadienyl (c-C6H7) radicals with 02 and NO were measured at 296 2 K. The c-C6H7 radicals were detected selectively by laser-induced fluorescence. The rate coefficient for the reaction of c-C6H7 with O-2, (4.4 +/- 0.5) x 10(-14) cm(3) molecule(-1) s(-1), was independent of the bath-gas (He) pressure (13-80 Torr). In the reaction of c-C6H7 with NO, thermal equilibrium among c-C6H7, NO, and C6H7NO was observed. The forward and reverse reactions were in the falloff region, and the equilibrium constant was (1.5 +/- 0.6) x 10(-15) cm(3) molecule(-1). (C) 2007 Elsevier B.V. All rights reserved.
Rate constants for the reactions of free radicals with oxygen in solution
作者:B. Maillard、K. U. Ingold、J. C. Scaiano
DOI:10.1021/ja00353a039
日期:1983.7
The kinetics of the rections of several freeradicals with oxygen have been examined in solution at 300 K using laser flash photolysis techniques. The reactions of resonance-stabilized radicals are only slightly slower than those of nonstabilized radicals: for example, for tert-butyl (in cyclohexane), 4.93 x 10/sup 9/; benzyl, 2.36 x 10/sup 9/ (in cyclohexane); cyclohexadienyl (in benzene), 1.64 x
已经使用激光闪光光解技术在 300 K 的溶液中检查了几种自由基与氧反应的动力学。共振稳定自由基的反应仅比不稳定自由基的反应稍慢:例如,对于叔丁基(在环己烷中),4.93 x 10/sup 9/;苄基,2.36 x 10/sup 9/(在环己烷中);环己二烯基(在苯中),1.64 x 10/sup 9/ M/sup -1/ s/sup -1/。丁基锡 (n-Bu/sub 3/Sn.) 自由基的反应速度异常快 (7.5 x 10/sup 9/ M/sup -1/ s/sup -1/),这一事实已初步归因于由于重原子效应而放宽自旋选择规则。1张桌子。
The reactivity of ketyl and alkyl radicals in reactions with carbonyl compounds
作者:E. T. Denisov
DOI:10.1007/bf02494263
日期:1998.11
parabolic model of bimolecular radical reactions was used for analysis of the hydrogen transfer reactions of ketyl radicals: >C·OH+R1COR2→>C=O+R1R2C·OH. The parameters describing the reactivity of the reagents were calculated from the experimental data. The parameters that characterize the reactions of ketyl and alkyl radicals as hydrogen donors with olefins and with carbonyl compounds were obtained: >C·OH
Laser Flash Photolysis of 2,2'-Dithiobls(pyridine N-oxide): Reactivity of N-Oxypyridyl-2-thio Radical
作者:Maksudul M. Alam、Akira Watanabe、Osamu Ito
DOI:10.1111/j.1751-1097.1996.tb02991.x
日期:1996.1
2′‐dithiobis(pyridine N‐oxide) and relatedcompounds have been studied. The transient absorption band at 360 nm was attributed to the radical in which the unpairedelectron mainly localizes on the S atom (N‐oxypyridyl‐2‐thio radical). The reactivities of the radical for conjugated dienes are lower than those of the pyridyl‐2‐thio radical, suggesting that a considerable unpairedelectron density on the S atom delocalizes
摘要:研究了 2,2'-二硫代双(吡啶 N-氧化物)和相关化合物的纳秒激光闪光光解产生的自由基的反应动力学。360 nm 处的瞬态吸收带归因于未配对电子主要位于 S 原子上的自由基(N-oxypyridyl-2-thio 自由基)。共轭二烯自由基的反应活性低于吡啶基-2-硫基自由基,这表明 S 原子上相当大的未配对电子密度离域到 N-氧吡啶部分。氢键溶剂和阳离子的加入可以加速自由基与共轭二烯的加成反应速率,这可以稳定 N+-O- 正则结构,增加 S 原子上的未配对电子密度。通过 N-羟基吡啶-2-硫酮的光解,N-O 键主要解离产生吡啶基-2-硫基。通过其阴离子的光解,发生光射出,然后发生 N-O 键裂变,产生吡啶-2-硫酮。
Heats of formation of radicals and molecules by a photoacoustic technique
作者:T. J. Burkey、M. Majewski、D. Griller
DOI:10.1021/ja00269a017
日期:1986.4
Description de la methode photoacoustique. Pour l'illustrer on mesure les energies de dissociation pour la liaison Sn-H dans n-Bu 3 SnH, la liaison C 3 -H dans le cyclohexadiene-1,4 et la liaison C 2 -H dans l'ether diethylique. Mesure des rendements quantiques pour la photolyse du peroxyde de di-t-butyle
描述 de la methode photoacoustique。把 l'illustrer 倒在测量 les energies de dissociation pour la liaison Sn-H dans n-Bu 3 SnH、la liaison C 3 -H dans le cyclohexadiene-1,4 et la liaison C 2 -H dans l'ether diethylique。Mesure des rendements quantiques pour la photolyse du peroxyde de di-t-bute
Chemistry of organosilicon compounds. 178. Electron spin resonance and chemical studies on the 6-(trimethylsilyl)cyclohexadienyl and related radicals
作者:Mitsuo Kira、Hisashi Sugiyama、Hideki Sakurai
DOI:10.1021/ja00359a013
日期:1983.10
Spectres RPE des radicaux t-butyl-6-, trimethylsilyl-6- et trimethylgermyl-6 et deuterio-6 cyclohexadienyles et discussion de la relation entre les parametres RPE et la structure de ces radicaux
Specters RPE des radicaux t-butyl-6-, trimethylsilyl-6- et trimethylgermyl-6 et deuterio-6 cyclohexadinyles et Discussion de la relationship entre les parametres RPE et la structure de ces radicaux