Qiu Zaozao, Xie Zuowei
Department of Chemistry and Center of Novel Functional Molecules, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China.
J Am Chem Soc. 2009 Feb 18;131(6):2084-5. doi: 10.1021/ja809389k.
Transition metal mediated multicomponent cross-coupling reactions are a powerful strategy to assemble complex molecules from very simple precursors in a single operation. This Communication reports a nickel-mediated three-component cycloaddition reaction of carboryne with alkenes and alkynes giving dihydrobenzocarborane derivatives with excellent chemo- and regioselectivity. A reaction mechanism involving sequential alkene and alkyne insertion, followed by reductive elimination, is proposed. The key intermediate of nickelacyclopentane was isolated and confirmed by single-crystal X-ray analyses. This work furnishes a new method for the preparation of substituted dihydrobenzocarboranes that are difficult to obtain by other methods.
过渡金属介导的多组分交叉偶联反应是一种强大的策略，可在单一操作中从非常简单的前体组装复杂分子。本通讯报道了镍介导的碳硼炔与烯烃和炔烃的三组分环加成反应，生成具有优异化学选择性和区域选择性的二氢苯并碳硼烷衍生物。提出了一种涉及烯烃和炔烃顺序插入，然后进行还原消除的反应机理。镍环戊烷的关键中间体通过单晶X射线分析得以分离和确认。这项工作提供了一种制备其他方法难以获得的取代二氢苯并碳硼烷的新方法。
