The Skaggs Institute for Chemical Biology and Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
J Am Chem Soc. 2010 Apr 28;132(16):5574-5. doi: 10.1021/ja101032j.
3-Hydroxyoxindoles are common structural motifs found in a vast array of natural and biologically active molecules. Most catalytic methods for the asymmetric syntheses of these compounds require the use of transition-metal catalysts. In contrast, alternative catalytic procedures involving organocatalysis are scarce. Herein we disclose a novel aminooxygenation of oxindoles with nitrosobenzene catalyzed by a newly designed quinidine dimer to afford the desired products in good yields with enantioselectivities up to 96%. These reactions allow one to construct a C-O bond at the C(3) position of oxindoles with the creation of an oxygen-containing tetrasubstituted chiral center and provide a new, general organocatalytic approach to the synthesis of 3-hydroxyoxindole derivatives.
3-羟基氧吲哚是在大量天然和生物活性分子中常见的结构基序。这些化合物的不对称合成的大多数催化方法都需要使用过渡金属催化剂。相比之下，涉及有机催化的替代催化程序则很少。在此，我们披露了一种新的由新设计的奎尼定二聚体催化的氮苯氧化吲哚的氨基氧反应，以高产率和高达 96%的对映选择性得到所需产物。这些反应允许在吲哚的 C(3)位置构建 C-O 键，同时形成含氧的四取代手性中心，并提供了一种新的、通用的有机催化方法来合成 3-羟基氧吲哚衍生物。
