Linear free energy ortho-correlations in the reactions of some 2-bromo-5-nitro-3-X-thiophenes with primary and secondary amines in benzene
作者:Giovanni Consiglio、Vincenzo Frenna、Susanna Guernelli、Gabriella Macaluso、Domenico Spinelli
DOI:10.1039/b111544h
日期:2002.4.29
The kinetics of SNAr reactions of some 2-bromo-3-X-5-nitrothiophenes (X = Me, H, Br, CONH2, CO2Me, COMe, SO2Me, CN and NO2) with some primary (n-butylamine and benzylamine) and secondary (pyrrolidine, piperidine, morpholine and N-benzylamine) amines have been measured in benzene as a function of nucleophile concentration. Most of the reactions studied show apparent kinetic constants little affected
一些2-溴-3-X-5-硝基噻吩(X = Me,H,Br,CONH 2,CO 2 Me,COMe,SO 2 Me,CN和NO 2)的S N Ar反应动力学(正丁胺 和 苄胺)和次要(吡咯烷, 哌啶, 吗啉 和 N-苄胺) 胺类 已被测量 苯亲核试剂浓度的函数。所研究的大多数反应表明,表观动力学常数几乎不受或不受增加的影响。胺 浓度,表明整体反应速率受生成的 反应中间体。X = Br和CN的底物与两者的反应伯胺被证明是碱催化的。为这些取代基计算的k 3 B / k -1值与中间分解的碱催化的假设不一致,强烈暗示了反应路径第一步的催化。