作者:Mario Ellwart、Ilya S. Makarov、Florian Achrainer、Hendrik Zipse、Paul Knochel
DOI:10.1002/anie.201603923
日期:2016.8.22
Readily prepared allylic zinc halides undergo SN2‐type substitutions with allylic bromides in a 1:1 mixture of THF and DMPU providing 1,5‐dienes regioselectively. The allylic zinc species reacts at the most branched end (γ‐position) of the allylic system furnishing exclusively γ,α′‐allyl–allyl cross‐coupling products. Remarkably, the double bond stereochemistry of the allylic halide is maintained during
现成的烯丙基卤化锌在THF和DMPU的1:1混合物中用烯丙基溴进行S N 2型取代,可选择性地提供1,5二烯。烯丙基锌物种在烯丙基体系的最分支末端(γ位置)反应,专门提供γ,α'-烯丙基-烯丙基交叉偶联产物。值得注意的是,烯丙基卤的双键立体化学在交叉偶联过程中得以保持。还可以耐受几个官能团(酯,腈)。烯丙基锌试剂的这种交叉偶联可以扩展到炔丙基和苄基卤化物。DFT计算显示了氯化锂在该替代中的重要性。