Mechanistic studies on the reactions of trimethylsilanide and trimethylstannylide ions with haloarenes in hexamethylphosphoramide
作者:Al Postigo、Santiago E. Vaillard、Roberto A. Rossi
DOI:10.1016/s0022-328x(02)01572-3
日期:2002.8
former, compared with the more reactive, and less selective Me3Si− ions. When 1-allyloxy-2-halobenzenes (X=Cl, I) are allowed to react with Me3Sn− ions in HMPA, an ipso substitution product 6 is obtained, in addition to stannylated products on the allylic moiety. This reaction proceeds by a HME process, as opposed to the same reaction carried out in liquid ammonia, where (2,3-dihydro-benzofuran-3-yl
大的正ρ选自Me得到的值3中号-离子与适当取代的氯代芳烃(4.1±0.1,以及对于M = Sn和硅分别2.94±0.02)可占强的负电荷的存在下反应取代反应的过渡态。这些ρ为我值3的Sn -和Me 3硅- ARX的亲核攻击为前者的总体更大的选择性提供的证据,与更具反应性,并且选择性较差我比较3硅-离子。当1-烯丙氧基-2-卤代苯(X = Cl,I)与Me 3 Sn反应-离子HMPA,一个本位取代产物6获得,除了stannylated产品上的烯丙基基团。与在液氨中进行的相同反应相反,该反应通过HME方法进行,其中通过S RN 1机理高产率地提供了(2,3-二氢-苯并呋喃-3-基甲基)-三甲基锡烷(4)。。我的反应3硅-与1-烯丙氧基-2-碘苯在HMPA,得到仅离子本位取代产物,即2-(烯丙氧基-苯基) -三甲基硅烷(11)中,通过高价的硅物种的中间性。