Umpolung of Carbonyl Groups as Alkyl Organometallic Reagent Surrogates for Palladium-Catalyzed Allylic Alkylation
作者:Dianhu Zhu、Leiyang Lv、Chen-Chen Li、Sosthene Ung、Jian Gao、Chao-Jun Li
DOI:10.1002/anie.201809112
日期:2018.12.10
carbon nucleophiles is difficult and remains a major challenge. Reported here is a highly chemo‐ and regioselective direct palladium‐catalyzed C‐allylation of hydrazones, generated from carbonyls, as a source of umpolung unstabilized alkyl carbanions and surrogates of alkyl organometallic reagents. Contrary to classical allylation techniques, this umpolung reaction utilizes hydrazones prepared not
钯催化的非稳定碳亲核试剂的烯丙基烷基化是困难的,并且仍然是一个重大挑战。此处报道的是羰基生成的的高度化学和区域选择性直接钯催化的C的C-烯丙基化,其为未稳定的烷基化碳烷基碳负离子和烷基有机金属试剂的替代物。与经典的烯丙基化技术相反,该紧缩反应利用不仅由芳基醛而且还由烷基醛和酮制备的作为可再生原料。通过提供高效,选择性的催化替代方法来代替传统的高反应性烷基有机金属试剂的使用,该策略可补充钯催化的不稳定的亲核试剂与烯丙基亲电试剂的偶联。