Lifetimes and UV-visible absorption spectra of benzyl, phenethyl, and cumyl carbocations and corresponding vinyl cations. A laser flash photolysis study
Gas-phase ion-molecule reaction of alpha-phenylvinyl cation towards substituted benzenes in the environment of an ITMS
作者:Michela Begala、Graziella Tocco
DOI:10.1002/jms.1997
日期:2011.11
Ion-moleculereactions between the alpha-phenylvinyl cation (alpha-PVC) and mono-substituted benzenes have been investigated using a quadrople ion-trap mass spectrometer. The alpha-PVC, generated by chemical ionization from phenylacetilene, was found to react selectively with mono-substituted benzenes bearing electron withdrawing groups to give the product ions [M + 103](+) and the trans-vinylating
The torsional barrier around the phenyl–C<sup>+</sup>bond in phenylcarbenium ions
作者:Roland Jost、Jean Sommer
DOI:10.1039/p29830000927
日期:——
The barrier to rotation around the phenyl–carbenium carbon bond in a series of carbenium ions R1R2C+Ph (with R1 and/or R2= H, CH3, cyclopropyl, and C6H4X) has been measured by complete line-shape analysis of the n.m.r. spectra or by the spin saturation transfer method. ΔG‡ Values range from 36 to 78 kJ mol–1. The results are discussed in terms of steric and electronic contributions and the relationship
在一系列碳正离子R 1 R 2 C + Ph(其中R 1和/或R 2 = H,CH 3,环丙基和C 6 H 4 X)中绕苯基碳原子碳键旋转的障碍为通过对nmr光谱进行完整的线形分析或通过自旋饱和转移法进行测量。Δ ģ ‡值的范围从36至78千焦耳摩尔-1。结果在空间和电子的贡献的术语和的关系讨论13与σ碳正中心的c。化学位移Ç +的值对-取代基被分析。
Structural effects in solvolytic reactions. 45. Carbon-13 NMR studies of carbocations. 9. Variation of the cationic carbon chemical shifts with increasing electron demand in 1,1-diaryl-1-ethyl carbocations. Importance of the inductive localized .pi.-polarization effect in causing deviations from linearity
作者:Herbert C. Brown、Mariappan Periasamy、P. Thirumalai Perumal、David P. Kelly、Joseph J. Giansiracusa
DOI:10.1021/ja00358a019
日期:1983.9
Etude systematique des effets de substituants sur les carbocations aryl. On observe dans certains cas une deviation par rapport a la linearite entre les deplacements chimiques du carbone cationique et la constante GC + et l'on suggere que de telles deviations sont dues a une polarisation π localisee
Etude systematique des effets de substituants sur les carbocations aryl。在观察 dans 某些 cas une 偏差 par rapport a la linearite entre les deplacements chimiques du carbone cationique et la constante GC + et l'on suggere que de Telles 偏差 不存在极化 π localisee