Einfache Synthesen von 1,2-Diaryl- und Triarylethenen mit trägergebundenen Fluoridbasen
作者:D. Hellwinkel、K. Göke、R. Karle
DOI:10.1055/s-1994-25617
日期:——
Facile Syntheses of 1,2-Diaryl- and Triarylethenes with Supported Fluoride Bases Differently substituted arenecarbaldehydes, mainly benzaldehydes, can be very efficiently condensed with a wide variety of methylbenzenes having an electron-withdrawing group in the para-position, as well as with fluorenes, xanthene, cyclopentadienes and indenes by using a standardized KF- or CsF-Al2O3 base system in dimethylformamide.
Dynamic NMR as a Nondestructive Method for the Determination of Rates of Dissociation. XIII. Sulfur Inversion in 9,9-Dialkyl-10-mesitylthioxanthenium Salts
作者:Michinori Oki、Yasuhisa Yamada
DOI:10.1246/bcsj.61.1181
日期:1988.4
The sulfur-inversion in the title compound (alkyl=ethyl) was found to take place with the following activation parameters by dynamic NMR spectroscopy: ΔH\eweq=23.8±0.2 kcal mol−1, ΔS\eweq=2.6±0.4 cal mol−1 K−1. The significance of the near zero entropy of activation is discussed. The mesityl group in the title compounds also showed restricted rotation of which barrier to rotation was estimated to be 14 kcal mol−1 at 318 K for the compound where the alkyl is a methyl.
通过动态核磁共振波谱发现标题化合物(烷基=乙基)中的硫转化发生在以下活化参数下:ΔH\eweq=23.8±0.2 kcal mol−1,ΔS\eweq=2.6±0.4 cal mol−1 1 K−1。讨论了接近零的激活熵的重要性。标题化合物中的异三叉基也显示出旋转受限,对于烷基为甲基的化合物,在 318 K 下估计旋转势垒为 14 kcal mol−1。
REAGENT FOR ENHANCING GENERATION OF CHEMICAL SPECIES
申请人:TOYO GOSEI CO., LTD.
公开号:US20150099893A1
公开(公告)日:2015-04-09
A reagent that enhances acid generation of a photoacid generator and composition containing such a reagent is described.