Photolytic Generation and the Subsequent Dimerization of 4-Alkyl-1-methylpyridinyl Radicals in Solution as Studied by Steady-state and Kinetic ESR Spectroscopy
4-alkyl-1-methylpyridinyl (alkyl=methyl, ethyl, isopropyl, and t-butyl) radicals were generated photolytically from their dimers in solution. Hyperfine splitting constants for these radicals were assigned and the temperature dependence was discussed. Absolute dimerization rates of these radicals in the range of −50–−100 °C were determined by analyzing the ESR signal decay during the dark period. A nearly constant activation
1-甲基吡啶基和 4-烷基-1-甲基吡啶基(烷基 = 甲基、乙基、异丙基和叔丁基)自由基是由它们的二聚体在溶液中光解产生的。指定了这些自由基的超精细分裂常数,并讨论了温度依赖性。这些自由基在 -50–-100 °C 范围内的绝对二聚率是通过分析黑暗时期的 ESR 信号衰减来确定的。观察到五个自由基的二聚活化能几乎恒定,而频率因子随着 4-取代基的体积增大而降低,这在二聚的空间位阻方面进行了讨论。
Process for the recovery of acetic acid from compositions comprising acetic acid and water
申请人:BP Chemicals Limited
公开号:EP0506240A2
公开(公告)日:1992-09-30
The use of an iodide compound of Group IA or Group IIA of the Periodic Table of the Elements or of hydrogen or aluminium to suppress the volatility of water relative to acetic acid in a process for the recovery of acetic acid from a composition comprising acetic acid and water by partitioning and separating the composition into vapour and liquid phases, with the iodide compound in the liquid phase.
在从由醋酸和水组成的组合物中回收醋酸的工艺中,使用元素周期表第 IA 组或第 IIA 组或氢或铝的碘化物化合物来抑制水相对于醋酸的挥发性,方法是将组合物分成气相和液相,碘化物化合物在液相中。
Aminomethinylation of 4-alkyl and 4-benzylpyridines - formation of stable enammonium salts and reduction to 2-(pyrid-4-yl)-propanol
作者:Hans-Joachim Schulz、J. Liebscher
DOI:10.1002/prac.19933350119
日期:——
Takahashi; Satake, Yakugaku Zasshi/Journal of the Pharmaceutical Society of Japan, 1952, vol. 72, p. 1183,1186
作者:Takahashi、Satake
DOI:——
日期:——
Takahashi; Satake, Yakugaku Zasshi/Journal of the Pharmaceutical Society of Japan, 1955, vol. 75, p. 14,18