Catalytic Enantioselective [3 + 2]-Cycloadditions of Diazoketone-Derived Aryl-Substituted Carbonyl Ylides
作者:David M. Hodgson、Rebecca Glen、Guy H. Grant、Alison J. Redgrave
DOI:10.1021/jo026307t
日期:2003.1.1
An evaluation of alpha-aryl-alpha-diazodiones in tandem carbonyl ylide formation-enantioselective [3 + 2]-cycloaddition reactions is described. Such substrates were designed to allow investigation of the electronic characteristics of the dipole upon asymmetric induction. Intramolecular cycloadditions (with a tethered alkene dipolarophile) were found to occur in good to quantitative yields, with a difference
描述了在串联羰基内酯形成-对映选择性[3 + 2]-环加成反应中对α-芳基-α-重氮二酮的评价。这样的衬底被设计成允许在不对称感应时研究偶极子的电子特性。发现分子内环加成反应(具有拴链的烯烃双极性亲和剂)以良好的定量产率发生,两个电子不同的重氮二酮8和9表现出ee差异。再次使用重氮二酮12和13与DMAD和芳基乙炔16-18进行分子间环加成。证明了电子学在决定环加成反应的结果中起着关键作用。观察到高达76%的对映选择性。