Regioselective Heck Vinylation of Electron-Rich Olefins with Vinyl Halides: Is the Neutral Pathway in Operation?
作者:Matthew McConville、Ourida Saidi、John Blacker、Jianliang Xiao
DOI:10.1021/jo802781m
日期:2009.4.3
Highly regioselective vinylation of electron-rich olefins by bromo- as well as chlorostyrenes is effected by palladium catalysis with either mono- or bidentate phosphines in a molecular solvent, with no need for halide scavengers, ionic liquids, or ionic additives. The use of the hemilabile 1,3-bis(diphenylphosphino)propane monoxide (dpppO) as a ligand led to faster reactions of more challenging 2-substituted
溴和氯苯乙烯对富电子烯烃的高度区域选择性乙烯基化是通过在分子溶剂中用单或二齿膦进行钯催化来实现的,不需要卤化物清除剂,离子液体或离子添加剂。半不稳定的1,3-双(二苯基膦基)丙烷一氧化碳(dpppO)作为配体的使用导致更具挑战性的2-取代乙烯基醚的反应更快,并降低了Pd的负载量。与相关的芳基化反应相反,证据表明乙烯基化可能通过中性的Heck机制进行。