1,3-Migration of a phenyl group in the conversion of (Me3Si)2(PhMe2Si)CSiMePhX into (Me3Si)2(Ph2MeSi)CSiMe2Y species
作者:Colin Eaborn、Anna Kowalewska、Wlodzimierz Stanczyk
DOI:10.1016/s0022-328x(97)00697-9
日期:1998.6
which the anchimerically-assisted departure of X− gives the Ph-bridged cation [(Me3Si)2MePh]+ which is attacked by the nucleophile at the less hindered centre bearing two Me groups rather than that bearing one Me and one Ph group, with the outcome determined by kinetic rather than thermodynamic factors. Both (Me3Si)2(Ph2MeSi)CSiMe2Br and its isomer (Me3Si)2(PhMe2Si)CSiMePhBr react with AgBF4 in CH2Cl2
发现(Me 3 Si)2(PhMe 2 Si)CSiMePhX类型的化合物与亲电试剂反应生成非常主要的重排产物(Me 3 Si)2(Ph 2 MeSi)CSiMe 2 Y处境不利,可以在一个机构而言,其中X的anchimerically辅助出发合理化-使PH-桥接阳离子[(ME 3 Si)的2麦菲] +它在受阻较轻的中心由带有两个Me基团的亲核试剂攻击,而不是由带有一个Me和一个Ph基团的亲核试剂攻击,其结果由动力学而非热力学因素决定。(Me 3 Si)2(Ph 2 MeSi)CSiMe 2 Br及其异构体(Me 3 Si)2(PhMe 2 Si)CSiMePhBr均与AgBF 4在CH 2 Cl 2或Et 2 O中反应,得到95%以上的氟化物(Me 3 Si)2(Ph 2 MeSi)CSiMe 2 F.溴化物(Me 3 Si)2的反应(PhMe中2 Si)的CSiMePhBr用的AgO 2