A Practical Procedure for Iron-Catalyzed Cross-Coupling Reactions of Sterically Hindered Aryl-Grignard Reagents with Primary Alkyl Halides
作者:Chang-Liang Sun、Helga Krause、Alois Fürstner
DOI:10.1002/adsc.201301089
日期:2014.4.14
Although iron‐catalyzed cross‐coupling reactions of arylmagnesium halides with alkyl halides are well established and proceed effectively under a variety of experimental conditions, they often find limitations when working with sterically hindered aryl‐Grignard reagents. Outlined in this paper is a practical solution that allows this gap in coverage to be filled. Specifically, it is shown that bis
尽管已经建立了芳基卤化镁与烷基卤化物的铁催化交叉偶联反应,并且可以在各种实验条件下有效地进行,但在使用位阻芳基格氏试剂时,它们经常会发现局限性。本文概述的是一种实用的解决方案,可以弥补覆盖范围中的这一空白。具体地,表明双(二乙基膦基)乙烷(depe)对Fe(+2)产生了有效的配位环境。这种可商购的配体足够纤细,即使邻位,邻位也不会干扰铁中心的负载-二取代的芳基卤化镁,但能够防止所得的有机铁物质过早还原偶联,这似乎也不是碱性的。该反应与各种极性官能团以及含有β-杂原子取代基的底物兼容。而且,该方法甚至允许包埋的新戊基亲电子试剂与溴化间苯二甲酸镁一样大,而供体芳基化,而仲烷基卤化物趋于消除。