Reaction between aminoalkyl radicals and akyl halides: Dehalogenation by electron transfer?
作者:J. Lalevée、J.P. Fouassier、N. Blanchard、K.U. Ingold
DOI:10.1016/j.cplett.2011.05.055
日期:2011.7
diffusion-controlled limit. For the less reactive halide, CH2Br2, the reaction rate is increased substantially by the addition of acetonitrile as a co-solvent. It is tentatively concluded that these reactions occur by electron-transfer from the aminoalkyl to the organohalide with formation of the iminium ion, Et2N+CHCH3 (NMR detection), halide ion and a halomethyl radical, e.g., CCl3 and CHCl2 (ESR, spin-trapping detection)
氨基烷基,例如Et 2 NCHCH 3的氧化电位低,因此是强大的还原剂。我们发现Et 2 NCHCH 3与CCl 4和CBr 4在过氧化二叔丁基中反应,其双分子速率常数(通过LFP测量)接近或等于扩散控制的极限。对于反应性较低的卤化物CH 2 Br 2,通过加入乙腈作为助溶剂,可显着提高反应速率。初步得出结论,这些反应是通过电子从氨基烷基转移到有机卤化物上而形成亚胺离子,Et 2 N + CHCH 3(NMR检测),卤化物离子和卤代甲基,例如CCl 3和CHCl 2(ESR,自旋捕获检测)。