Spectroscopy and Absolute Reactivity of Ketenes in Acetonitrile Studied by Laser Flash Photolysis with Time-Resolved Infrared Detection
作者:Brian D. Wagner、Bradley R. Arnold、Gerald S. Brown、Janusz Lusztyk
DOI:10.1021/ja964155b
日期:1998.3.1
to the Swain−Lupton field (F) and resonance (R) effect substituent parameters was unsatisfactory, whereas the correlation to the inductive substituent parameter (σI) of Charton gave excellent results. This suggests that the asymmetric stretching frequency of substituted ketenes depends mainly on the inductive (i.e., field) effect of the substituents. The mechanism and kinetics of the reactions of these
具有时间分辨红外瞬变检测 (LFP-TRIR) 的激光闪光光解已被用于研究由 α-重氮羰基前体在室温下在乙腈溶液中的 308 nm 光解制备的许多取代乙烯酮的红外光谱和反应性温度。实验乙烯酮不对称伸缩频率与 Swain-Lupton 场 (F) 和共振 (R) 效应取代基参数的相关性并不令人满意,而与 Charton 的感应取代基参数 (σI) 的相关性给出了极好的结果。这表明取代烯酮的不对称伸缩频率主要取决于取代基的感应(即场)效应。还研究了这些乙烯酮与各种胺在乙腈中的反应机理和动力学。通过 TRIR 观察到在仲胺与乙烯酮的 Cα 的亲核加成过程中形成的中间物质,被确定为两性离子叶立德或酰胺烯醇。这 ...