Kinetic Study and Analytical Application of the Hexadecyltrimethylammonium Bromide-Catalyzed Reaction of l-Fluoro-2,4-dinitrobenzene with Amines
作者:Michelle P. Wong、Kenneth A. Connors
DOI:10.1002/jps.2600720213
日期:1983.2
Arylation of amines by reaction with 1-fluoro-2,4-dinitrobenzene is catalyzed by micelles of cetrimonium bromide. This catalysis has been exploited to reduce the analysis time in the spectrophotometric determination of amines as their dinitrophenyl derivatives. The kinetics of the catalysis were studied for the five amines: alanine, phenylalanine, aniline, 4-methylaniline, and 4-methoxyaniline. The
Effect of Substituent on Regioselectivity and Reaction Mechanism in Aminolysis of 2,4-Dinitrophenyl X-Substituted Benzenesulfonates
作者:Ik-Hwan Um、Jin-Young Hong、Jin-Ah Seok
DOI:10.1021/jo048227q
日期:2005.2.1
a kinetic study for the nucleophilic substitution reactions of 2,4-dinitrophenyl X-substituted benzensulfonates (X = 4-MeO, 1a, and X = 4-NO2, 1c) with a series of primary amines in 80 mol % H2O/20 mol % DMSO at 25.0 °C. The reactions proceed through S−O and C−O bondfission pathways competitively. The fraction of the S−O bondfission increases as the attaching amine becomes more basic and the substituent
我们对的2,4-二硝基苯基X取代的benzensulfonates亲核取代反应的动力学研究报告(X = 4-的MeO,1A,和X = 4-NO 2,1C),在80摩尔%一系列伯胺的在25.0°C下,H 2 O / 20 mol%DMSO。反应通过S-O和C-O键裂变途径竞争地进行。S-O键裂变的分数随连接胺变得更碱性和取代基X从4-MeO变为4-NO 2而增加,表明区域选择性是由取代基X的电子性质以及胺的碱度决定的。已建议S-O键裂变通过加成中间体进行,其中速率确定步骤(RDS)的变化为p K a °= 8.9±0.1。取代基X的电子性质影响k N S - O和k 1值,但不影响k 2 / k - 1比和p K a°值明显。通过供电子取代基和亲电子中心之间的共振相互作用,稳定基态(GS)的原因是1a的反应性比1c降低。C-O键裂变的二阶速率常数与取代基X的电子性质不相关。距离效应和反应机理的性质被认为是造成这种不相关的原因。
The α-Effect in S<sub>N</sub>Ar Reaction of Y-Substituted-Phenoxy-2,4-Dinitrobenzenes with Amines: Reaction Mechanism and Origin of the α-Effect
作者:Hyo-Jin Cho、Min-Young Kim、Ik-Hwan Um
DOI:10.5012/bkcs.2014.35.8.2448
日期:2014.8.20
The α-Effect in SNAr Reaction of Aryloxy-2,4-dinitrobenzenes Bull. Korean Chem. Soc. 2014, Vol. 35, No. 8 2449stituted-phenoxy-2,4-dinitrobenzenes (1a-1g) with hydra-zine and glycylglycine as an α-nucleophile and a referencenormal-nucleophile, respectively to obtained further infor-mation on the origin of the α-effect in the S