Enantioselective organocatalytic aminomethylation of aldehydes:: A role for ionic interactions and efficient access to β2-amino acids
Enantioselective organocatalytic aminomethylation of aldehydes:: A role for ionic interactions and efficient access to β2-amino acids
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DOI：
10.1021/ja061731n
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发表时间：
2006-05-31
影响因子：
15
通讯作者：
Gellman, Samuel H.
中科院分区：
文献类型：
--
作者：
Chi, Yonggui;Gellman, Samuel H.
脯氨酸衍生的手性吡咯烷催化的醛与甲醛衍生的亚胺物种的有机催化Mannich加成反应提供了ee ≥90%的β-氨基醛.脯氨酸催化反应的机理分析表明，Mannich反应过渡态的非氢键离子相互作用可以影响立体化学结果。从我们的方法中得到的β-氨基醛带有邻近羰基的取代基，并且可以有效地转化为受保护的β2-氨基酸，其是显示有用的生物活性的β-肽折叠体的重要结构单元。
Organocatalytic Mannich addition of aldehydes to a formaldehyde-derivediminiumspecies catalyzed by proline-derived chiral pyrrolidines provides β-amino aldehydes with ≥90% ee. Mechanistic analysis of the proline-catalyzed reactions suggests that non-hydrogen-bonded ionic interactions at the Mannich reaction transition state can influence stereochemical outcome. The β-amino aldehydes from our process bear a substituent adjacent to the carbonyl and can be efficiently converted to protected β2-amino acids, which are important building blocks for β-peptide foldamers that display useful biological activities.