Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.
J Org Chem. 2012 Sep 7;77(17):7212-22. doi: 10.1021/jo301495a. Epub 2012 Aug 20.
Enantio- and diastereoselective one-pot synthesis of three- to seven-membered cis-azaheterocycles was achieved using a triggered asymmetric conjugate addition reaction of lithium amide with an enoate, followed by alkylation of the resulting lithium enolate with α,ω-dihaloalkane and N-alkylation. Isomerization of cis-azaheterocycles with a base yielded the trans-product, constituting a one-pot synthesis of cis-azacycles and a two-step synthesis of trans-azacycles. The four-step asymmetric synthesis of nemonapride highlights the general utility of the method.
通过烯酰胺与烯酸酯的引发不对称共轭加成反应,接着用α,ω-二卤代烷和 N-烷基化试剂对生成的锂烯醇化物进行烷基化,实现了三至七元内消旋氮杂环的对映选择性和非对映选择性一锅合成。用碱进行顺式氮杂环异构化得到反式产物,构成了顺式氮杂环的一锅合成和反式氮杂环的两步合成。nemonapride 的四步不对称合成突出了该方法的通用性。