Efficient Synthesis of Medium-Sized Rings Incorporating Indole or Pyrrole Units by Samarium Diiodide Induced Cyclizations
作者:Virginie Blot、Hans-Ulrich Reißig
DOI:10.1002/ejoc.200600743
日期:2006.11
Samarium diiodide promoted the intramolecular reductive couplings of N-alkylated indole and pyrrole derivatives 9–12 and 14 to afford products 15–19 that incorporate seven- and eight-membered rings. They were obtained in good yields and generally with excellent diastereoselectivities. Up to four contiguous stereogenic centres are controlled in this transformation, which is explained by a highly ordered
二碘化钐促进了 N-烷基化吲哚和吡咯衍生物 9-12 和 14 的分子内还原偶联,以提供包含七元环和八元环的产物 15-19。它们以良好的产率获得并且通常具有优异的非对映选择性。在这种转变中最多控制四个连续的立体中心,这可以通过高度有序的过渡结构来解释,其中钐醇化物部分更喜欢赤道位置。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)