Anilinolysis of nitro-substituted diphenyl ethers in acetonitrile: The effect of some ortho-substituents on the mechanism of S<sub>N</sub>
Ar reactions
作者:Chukwuemeka Isanbor、Thomas A. Emokpae
DOI:10.1002/kin.20457
日期:2010.1
than that of 2,6‐(CH3)2. However, the reactions with 2e are base catalyzed whereas those of 2d are not. The corresponding reactions with aniline 2a (Y = H) and mono‐ortho methyl‐substituted aniline 2b (Y = CH3) are wholly base catalyzed. Only with the dinitro substrates, an uncatalyzed reaction is observed and when X = 2,6‐(NO2)2 this pathway takes all the reaction flux. A rationale is provided for the
率数据报道了一系列的X苯基2,4,6-三硝基苯醚的反应中1A-E [X = H,4-NO 2,2-NO 2,2,4-(NO 2)2,或2,6-(NO 2)2 ]与取代的苯胺2A-E [Y = H,2-CH 3,2,4-(CH 3)2,2,6-(CH 3)2,或N-通道3在乙腈中作为溶剂。对于单个胺,动力学数据表明,即使存在双邻位取代,在母体分子的1位上几乎没有位阻进攻。但是,对于每种底物,都有明显的空间相互作用的证据。这种导致速率降低的效应对于2,6-二甲基苯胺2d(2,6-(CH 3)2)和N-甲基苯胺2e(Y = N-CH 3)非常严重,N-CH 3在大多数情况比2,6-(CH 3)2略高。但是,与2e的反应是碱催化的,而2d的反应是碱催化的不是。与苯胺2a(Y = H)和单邻甲基取代的苯胺2b(Y = CH 3)的相应反应完全被碱催化。仅在使用二硝基底物的情况下,观察到未催化的反应,并且当X