Structures of Reactive Nitrenium Ions: Time-Resolved Infrared Laser Flash Photolysis and Computational Studies of Substituted <i>N</i>-Methyl-<i>N</i>-arylnitrenium Ions
作者:Sanjay Srivastava、Patrick H. Ruane、John P. Toscano、Michael B. Sullivan、Christopher J. Cramer、Dominic Chiapperino、Elizabeth C. Reed、Daniel E. Falvey
DOI:10.1021/ja001184k
日期:2000.8.1
N-(4-methylphenyl)-N-methylnitrenium ion) were generated through photolysis of the appropriately substituted 1-aminopyridinium salt. Laser flash photolysis using UV−vis detection as well as photoproduct analysis verified that the expected nitrenium ions were formed cleanly and rapidly following photolysis. Laser flash photolysis with time-resolved infrared detection allowed for structural characterization of the
一系列对位取代的N-甲基-N-苯基氮离子(N-(4-biphenylyl)-N-methylnitrenium ion, N-(4-chlorophenyl)-N-methylnitrenium ion, N-(4-methoxyphenyl)-N -甲基氮鎓离子和N-(4-甲基苯基)-N-甲基氮鎓离子)通过适当取代的1-氨基吡啶鎓盐的光解产生。使用 UV-vis 检测和光产物分析的激光闪光光解验证了预期的氮离子在光解后干净且快速地形成。具有时间分辨红外检测的激光闪光光解允许通过观察 1580-1628 cm-1 区域内的对称芳香 CC 拉伸来表征氮鎓离子。特定频率反映了每个苯基硝基鎓离子中存在的醌型特征的程度(即,氮烯离子与 4-亚氨基环六-2,5-二烯基阳离子相似的程度)。4-甲氧基衍生物显示出最高频率的 CC 拉伸,表明这种强烈的 π 供电子...