Kinetic and equilibrium studies of the ambident reactivity of aniline, and some derivatives, towards 4,6-dinitrobenzofuroxan † ‡
作者:Michael R. Crampton、Lynsey C. Rabbitt
DOI:10.1039/a903123e
日期:——
The reactions of aniline and its derivatives at the 7-position of 4,6-dinitrobenzofuroxan (DNBF) may result in rapid reaction via the nitrogen centre to give anionic σ-adducts. Equilibrium constants for these reactions in DMSO are reported and correlate with pKa values of the corresponding anilinium ions. Slower reactions are observed involving electrophilic substitution by DNBF at ring-carbon atoms
苯胺及其衍生物在4,6-二硝基苯并呋喃(DNBF )的7位反应可能会导致通过氮中心的快速反应而生成阴离子σ加合物。报告了在DMSO中这些反应的平衡常数,并与p K a相关相应的苯胺离子的值。观察到较慢的反应,其中包括在苯胺衍生物的环碳原子上被DNBF亲电取代。报告速率常数。这些反应产生两性离子碳键合的σ-加合物,在过量苯胺的存在下,它们与去质子化形式快速平衡。已经测量了该酸碱过程的平衡常数,并表明带负电荷的DNBF部分相对于氢而言是吸电子的。
BUNCEL E.; RENFROW R. A.; STRAUSS M. J., J. ORG. CHEM., 52,(1987) N 4, 488-495