Absolute Rates of Intermolecular Carbon−Hydrogen Abstraction Reactions by Fluorinated Radicals
作者:Alexander B. Shtarev、Feng Tian、William R. Dolbier,、Bruce E. Smart
DOI:10.1021/ja990521q
日期:1999.8.1
kinetic methodology, absolute rate constants for bimolecular hydrogen abstraction from a variety of organic substrates in solution have been obtained for the n-C4H9CF2CF2•, n-C4F9•, and i-C3F7• radicals. Fluorine substitution substantially increases the reactivity of alkyl radicals with respect to C−H abstraction, with the secondary radical being most reactive. A wide range of substrate reactivities (5200-fold)
使用竞争动力学方法,对于 n-C4H9CF2CF2•、n-C4F9• 和 i-C3F7• 自由基从溶液中的各种有机底物中提取双分子氢的绝对速率常数已经获得。氟取代显着增加了烷基自由基对 C-H 提取的反应性,二级自由基反应性最强。观察到了广泛的底物反应性(5200 倍),并根据热力学、极性、空间、立体电子和静电/场效应对各种 CH 抽象过渡态的相互作用进行了讨论。使用 DFT 方法计算了许多醚和醇的代表性碳氢键解离能。