Photolysis of Bromo- and Chloro-Substituted Benzyl Derivatives. Competition between Ionic and Radical Pathways
作者:Berta Košmrlj、Boris Šket
DOI:10.1021/jo0001481
日期:2000.10.1
solutions of tetrahydrofuran, acetonitrile, and cyclohexane. The effect of free radical inhibitor and metal hydrides on products formation as well as their ratio was analyzed to elucidate the reaction pathway. In the first step homolytic C-X bond cleavage occurs from a single excited state, resulting in a biradical pair. Further reaction path depends on the type of the halogen bonded and on the solvent polarity
在四氢呋喃,乙腈和环己烷溶液中研究了1-氟-2-卤代-1,2-二苯乙烷的光解作用。分析了自由基抑制剂和金属氢化物对产物形成及其比例的影响,以阐明反应途径。在第一步中,均一的激发态发生均质的CX键断裂,形成双自由基。进一步的反应路径取决于结合的卤素的类型和溶剂的极性。对于溴化物来说,自由基对笼中的电子转移显然比氯化物更快,并且与基于氯和溴的相对电负性所预期的相反。当自由基彼此接近时,它们落入离子或自由基产物通道。这受溶剂极性的影响,