The ipso fluorination of arylboronic acids and some derivatives with caesium fluoroxysulfate has been developed. The reaction proceeds with a wide range of functionalised aromatics and is strongly solvent dependent.
CLOUGH, JOHN M.;DIORAZIO, LOUIS J.;WIDDOWSON, DAVID A., SYNLETT,(1990) N2, C. 761-769
作者:CLOUGH, JOHN M.、DIORAZIO, LOUIS J.、WIDDOWSON, DAVID A.
DOI:——
日期:——
A new synthesis of aryl fluorides: the reaction of caesium fluoroxysulfate with arylboronic acids and derivatives
作者:Louis J. Diorazio、David A. Widdowson、John M. Clough
DOI:10.1016/s0040-4020(01)80478-6
日期:1992.1
The ipso fluorination of arylboronic acids and some derivatives with caesium fluoroxysulfate has been developed. The reaction proceeds with a wide range of functionalised aromatics and is strongly solvent dependent.
Electrophilic Substituent Constant σ<sup>+</sup> of Electron Donor Substituents in Nonpolar Media
作者:Alexander Oehlke、Alexander A. Auer、Katja Schreiter、Katja Hofmann、Franziska Riedel、Stefan Spange
DOI:10.1021/jo9000383
日期:2009.5.1
The electrophilic substituent constant σ+ was derived from the relative rate constants of the solvolysis of substituted α-cumyl chlorides in an acetone/water solvent mixture in the original work by Brown and Okamoto (J. Am. Chem. Soc.1958, 80, 4979). As an extension of this procedure, we were looking for methods to determine σ+ values in nonpolar media. We have calculated the exocyclic charges q(R)
亲电取代基常数σ +是从取代的α枯基氯化物的溶剂分解的相对速率常数衍生在丙酮/水溶剂混合物在原有的工作Brown和冈本(J.化学会会志。1958,80, 4979)。作为此过程的扩展,我们正在寻找确定非极性介质中σ +值的方法。我们已经计算出α-枯基阳离子(RC 6 H 4 CMe 2 +)的环外电荷q(R),作为间位和对位取代基的供电子能力的度量。紫外线吸收ν̃ max相似取代的硝基苯衍生物的一部分已经用于实验测量非极性介质中取代基R的给电子能力。ν之间的线性关系最大和Δ q(R)(= q(RC 6 H ^ 4 CME 2 +) - q(C 6 H ^ 5 CME 2 +))中的溶液获得。对于已经研究过的取代基和通过实验确定σ +的取代基,都可以实现非极性介质中电子给体容量的描述。以前很难。特别关注的是基于硼的取代基,其中供电子能力取决于硼原子的配位环境。