Selective synthesis of 5-or 6-aryl octahydrocyclopenta[b]pyrroles from a common precursor through control of competing pathways in a Pd-catalyzed reaction
Selective synthesis of 5-or 6-aryl octahydrocyclopenta[b]pyrroles from a common precursor through control of competing pathways in a Pd-catalyzed reaction
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DOI：
10.1021/ja0430346
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发表时间：
2005-06-22
影响因子：
15
通讯作者：
Wolfe, JP
中科院分区：
文献类型：
--
作者：
Ney, JE;Wolfe, JP
1与芳基溴的Pd/膦催化反应导致选择性合成6-芳基八氢环戊二烯并[B]吡咯（3）、相应的5-芳基异构体5、二芳基胺2或六氢环戊二烯并[B]吡咯4，这取决于膦配体的结构。这些转化对各种不同的芳基溴是有效的，并提供具有优异水平的非对映选择性（dr >= 20：1）的3-5。产物分布的变化被认为是来自于Pd催化剂结构对机械复杂反应中还原消除、β-氢化物消除、烯烃插入和烯烃置换过程的相对速率的影响。详细描述了膦配体结构对产物分布的影响，沿着分析了这些转化的拟议机制。
The Pd/phosphine-catalyzed reaction of 1 with aryl bromides leads to the selective synthesis of either 6-aryl octahydrocyclopenta[b]pyrroles (3), the corresponding 5-aryl isomers 5, diarylamine 2, or hexahydrocyclopenta[b]pyrrole 4 depending on the structure of the phosphine ligand. These transformations are effective with a variety of different aryl bromides and provide 3-5 with excellent levels of diastereo-selectivity (dr >= 20:1). The changes in product distribution are believed to derive from the influence of Pd-catalyst structure on the relative rates of reductive elimination, beta-hydride elimination, alkene insertion, and alkene displacement processes in a mechanistically complex reaction. The effect of phosphine ligand structure on product distribution is described in detail, along with analysis of a proposed mechanism for these transformations.