Catalytic Barbier-type reactions of lactones and esters mediated by the Mischmetall/SmI2(cat.) system or the Mischmetall/[SmI2/NiI2(cat′.)](cat.) system
作者:Marie-Isabelle Lannou、Florence Hélion、Jean-Louis Namy
DOI:10.1016/s0040-4039(02)01979-2
日期:2002.11
SmI2 in catalytic amounts together with Mischmetall as a coreductant, involving lactones or esters and a variety of organic halides (allylic, benzylic and alkyl), have been performed. With alkyl halides and five- or six-membered ring lactones, catalytic quantities of nickel diiodide (with respect to SmI2) must be added to achieve reactions. Thus, a ‘two-stage catalysis’ is carried out. Unexpectedly, it
已经进行了使用催化量的SmI 2和Mischmetall作为共引发剂的Barbier型反应,涉及内酯或酯以及各种有机卤化物(烯丙基,苄基和烷基)。对于烷基卤化物和五元或六元环内酯,必须添加催化量的二碘化镍(相对于SmI 2)以实现反应。因此,进行“两阶段催化”。出乎意料的是,发现在化学计量的量下,对于酯或未应变的内酯,Mischmetall / SmI 2(催化)体系比二碘化sa具有更高的反应活性。初步解释了NiI 2的催化作用。