Carbopalladation of allenic hydrocarbons.
作者:Mohammed Ahmar、Jean-Jacques Barieux、Bernard Cazes、Jacques Gore
DOI:10.1016/s0040-4020(01)89984-1
日期:1987.1
palladium-catalyzed coupling reaction of allenes, vinyl or aryl halides and stabilized carbanions is described : π-allyl palladium complexes are formed by addition of a vinyl or an aryl-palladium complex to an allenic hydrocarbon and trapped by the sodium enolate of diethyl malonate giving rise with good yields to β-butadienyl or β-styryl malonates. With monoalkyi allenes, the reaction is regiospecific with attack
描述了丙烯,乙烯基或芳基卤化物和稳定化碳负离子的钯催化偶联反应:π-烯丙基钯配合物是通过将乙烯基或芳基-钯配合物添加到烯丙烃中形成的,并被丙二酸二乙酯的烯醇化钠捕获β-丁二烯基或β-苯乙烯基丙二酸酯的收率高。对于单烷基亚丙基,该反应是区域特异性的,亲核试剂攻击中间的π-烯丙基配合物的未取代的碳,并且在许多情况下具有高度立体选择性,主要形成二烯的三取代双键的E构型。使用NOE差光谱法通过1 H NMR证明了该构型。