Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, USA.
J Am Chem Soc. 2012 Jul 4;134(26):10807-10. doi: 10.1021/ja304859w. Epub 2012 Jun 20.
Nitrogen-containing stereotriads, compounds with three adjacent stereodefined carbons, are commonly found in biologically important molecules. However, the preparation of molecules bearing these motifs can be challenging. Herein, we describe a modular oxidation protocol which converts a substituted allene to a triply functionalized amine of the form C-X/C-N/C-Y. The key step employs a Rh-catalyzed intramolecular conversion of the allene to a strained bicyclic methylene aziridine. This reactive intermediate is further elaborated to the target products, often in one reaction vessel and with effective transfer of the axial chirality of the allene to point chirality in the stereotriad.
含氮立体三联体是在生物重要分子中常见的具有三个相邻立体定义的碳原子的化合物。然而,带有这些结构的分子的制备可能具有挑战性。在此,我们描述了一种模块化的氧化方案,该方案将取代的丙二烯转化为形式为 C-X/C-N/C-Y 的三官能化胺。关键步骤采用 Rh 催化的丙二烯分子内环化反应,生成应变双环亚甲基氮丙啶。该反应中间体可进一步转化为目标产物,通常在一个反应容器中进行,并且丙二烯的轴向手性有效地转移到立体三联体中的点手性。