Restricted Rotation in Aromatic Ketones. I. Substituent Effects on the Barrier to Rotation about the Benzene-to-Carbonyl Bond
作者:Nobuo Nakamura、Michinori Oki
DOI:10.1246/bcsj.45.2565
日期:1972.8
Several aryl isopropyl ketones and aryl benzyl ketones were synthesized and their NMR spectra were recorded at various temperatures. Their temperature dependence was accounted for in terms of the restricted rotation about the benzene-to-carbonyl bond, whose free energies of activation at the coalescence temperatures varied from 9 to 15 kcal/mol according to the steric effect of ortho substituents,
合成了几种芳基异丙基酮和芳基苄基酮,并在不同温度下记录了它们的核磁共振谱。它们的温度依赖性是根据苯 - 羰基键的受限旋转来解释的,根据邻位取代基的空间效应,其在聚结温度下的活化自由能从 9 到 15 kcal/mol 不等,支撑效应间位取代基和侧链基团的空间效应。