The Effect of Lewis Acids on the Stereochemistry in the Ugi Three-Component Reaction with<scp>D</scp>-<i>lyxo</i>-Pyrroline
作者:Kimberly M. Bonger、Tom Wennekes、Dmitri V. Filippov、Gerrit Lodder、Gijsbert A. van der Marel、Herman S. Overkleeft
DOI:10.1002/ejoc.200800340
日期:2008.7
pyrrolidines was obtained by performing a tandem Staudinger/aza-Wittig/Ugi three-component reaction on a L-ribose-derived 4-azido aldehyde. In this paper we describe the effect of Lewis acids on the diastereoselectivity of the final Ugi three-component reaction step that the intermediate (D-lyxo-pyrroline) cyclic imine undergoes. When the Ugi reaction was performed in methanol almost exclusively pyrrolidines with
通过对 L-核糖衍生的 4-叠氮醛进行串联 Staudinger/aza-Wittig/Ugi 三组分反应,获得多羟基化吡咯烷文库。在本文中,我们描述了路易斯酸对中间体(D-lyxo-吡咯啉)环状亚胺所经历的最终 Ugi 三组分反应步骤的非对映选择性的影响。当 Ugi 反应在甲醇中进行时,几乎只形成了具有 2,3-顺式关系的吡咯烷。然而,在向 Ugi 反应混合物中加入路易斯酸后,会形成大量的 2,3-反式产物。这种影响的范围是通过评估一组不同的路易斯酸结合其他反应参数和羧酸/异氰化物组分的变化来探索的。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)