作者:Young-Wook Yoon、Seung-Woon Lee、Sang-Kuk Lee
DOI:10.5012/bkcs.2010.31.9.2479
日期:2010.9.20
Using a pinhole-type glass nozzle equipped for a corona-excited supersonic expansion (CESE), precursor 2,6-dichlorotoluene seeded in a large amount of inert carrier gas helium was discharged to produce jet-cooled but electronically excited benzyl-type radicals. The visible vibronic emission spectrum was recorded with a long-path monochromator to observe vibronic bands in the $D_1\rightarrow}D_0$ electronic transition of benzyl-type radicals. The spectral analysis revealed the generation of not only the 2,6-dichlorobenzyl radical as a typical product, but also the o-chlorobenzyl radical as an unexpected species, which indicates the possible molecular rearrangement in eliminating a chlorine atom from the benzene ring. A possible mechanism is proposed for the formation of the o-chlorobenzyl radical from the precurs or in the gas phase.
利用一个配备有电晕激发超音速膨胀(CESE)装置的针孔型玻璃喷嘴,将前驱体 2,6- 二氯甲苯在大量惰性载气氦中放电,产生喷射冷却但电子激发的苄基自由基。利用长路径单色仪记录可见振子发射光谱,观察苄基自由基的$D_1\rightarrow}D_0$电子转变中的振子带。光谱分析显示,不仅生成了典型产物 2,6-二氯苄基自由基,而且还生成了意外的邻氯苄基自由基,这表明在消除苯环上的一个氯原子时可能发生了分子重排。提出了从前驱体或在气相中形成邻氯苄基自由基的可能机制。