Catalytic Reduction and Intramolecular Cyclization of Haloalkynes in the Presence of Nickel(I) Salen Electrogenerated at Carbon Cathodes in Dimethylformamide
作者:Michael A. Ischay、Mohammad S. Mubarak、Dennis G. Peters
DOI:10.1021/jo052007a
日期:2006.1.1
Pentylidenecyclopentane can be conveniently prepared in up to 86% yield via the catalytic reduction of 1-iodo- or 1-bromo-5-decyne by [[2,2‘-[1,2-ethanediylbis(nitrilomethylidyne)]bis[phenolato]]-N,N‘,O,O‘]nickelate(I) electrogenerated at a carbon cathode in dimethylformamide containing tetramethylammonium tetrafluoroborate. This electrosynthesis can be accomplished at potentials for which the haloalkynes
通过[[2,2 ' -[1,2-乙二基双(亚硝甲基))]双[苯酚基]催化还原1-碘-或1-溴-5-癸炔可以方便地制备亚萘基环戊烷,产率高达86%。] -N,N ',O,O '在包含四氟硼酸四甲基铵的二甲基甲酰胺中的碳阴极上电生成的]镍酸酯(I)。该电合成可以在卤代炔是电惰性的电势下完成,并且可以在室温下30分钟内完成。尝试在类似条件下分别由1-卤代4-壬炔和11-卤代5-十一炔合成戊二烯环丁烷和戊二烯环己烷可提供非常低的收率(分别为2%和6%)。衍生自各种卤代炔烃的其他产物是二聚体,炔烃和1-炔烃。由1-卤代4-壬炔和11-卤代5-十一炔产生的二聚体(alkadiynes)的产率为80%至89%,而icosa-5,15-diyne(由1-卤代获得的二聚体)发现-5-decyne)的收率明显较低(≤13%)。炔烃和1-炔烃的产率分别为3-10%和2-3%。提出了一种机制方案,该方案涉及由镍(