First Asymmetric Synthesis and Determination of the Absolute Configuration of a Lignan Isolated fromVirola sebifera
作者:Dieter Enders、Mile Milovanovic、Elena Voloshina、Gerhard Raabe、Jörg Fleischhauer
DOI:10.1002/ejoc.200400885
日期:2005.5
The first asymmetric synthesis of a lignan isolated from the seeds of Virola sebifera, one of the most widely spread Myristicaceae species in Brazil, in four steps (48 % overall yield) and with excellent stereoselectivity (de, ee ≥ 96 %) is described. The key step is the asymmetric Michael addition of a lithiated enantiopure α-amino nitrile to an enone, followed by α-methylation and cleavage of the
描述了从 Virola sebifera 种子中分离出的木脂素的第一次不对称合成,该木脂素是巴西最广泛传播的肉豆蔻科物种之一,分四步(48% 总产率)并具有出色的立体选择性(de, ee ≥ 96%)。关键步骤是锂化对映体纯 α-氨基腈与烯酮的不对称迈克尔加成,然后是氨基腈的 α-甲基化和裂解。天然存在的 1,4-二酮的绝对构型由旋光法以及 CD 光谱和量子化学计算确定。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)