A method for generation of α-halo carbanions (carbenoids) from aryl α-haloalkyl sulfoxides with alkylmetals
作者:Tsuyoshi Satoh、Koji Takano
DOI:10.1016/0040-4020(95)01078-5
日期:1996.2
Ligand exchange reaction of simple aryl α-haloalkyl sulfoxides with alkyllithium and ethylmagnesium halide at low temperature was investigated. On treatment of aryl α-haloalkyl sulfoxide with n-BuLi, t-BuLi, or EtMgX exclusively sulfur-alkyl bond-cleavage took prace to afford α-halo carbanion (carbenoid). When this reaction was carried out without a proton source, the intermediate α-halo carbanion
研究了简单的芳基α-卤代烷基亚砜与烷基锂和乙基镁卤化物在低温下的配体交换反应。在用n-BuLi,t-BuLi或EtMgX处理芳基α-卤代烷基亚砜时,只有硫-烷基键断裂才可得到α-卤代碳负离子(类胡萝卜素)。当该反应在没有质子源的情况下进行时,中间体α-卤代碳负离子分解以高收率得到烯烃。发现亚砜的配体交换反应非常快,该反应可以用质子或氘源(内部淬灭)进行,得到烷基卤。该程序提供了一种制备α-氘代卤化物(卤素为F,Cl或Br)的新方法。