作者:Christoph Schneider、Christoph Börner、Ansgar Schuffenhauer
DOI:10.1002/(sici)1099-0690(199912)1999:12<3353::aid-ejoc3353>3.0.co;2-q
日期:1999.12
Enantiopure piperidines 4 may be accessed in very good overall yields and high stereoselectivity from the bifunctional products 2 of the silyloxy Cope rearrangement of chiral aldol products 1 by sequential nucleophilic addition of primary amines and subsequent hydrogenation. The reaction is proposed to proceed by initial imine formation followed by an intramolecular aza-conjugate addition to the α
可以从手性羟醛产物 1 的甲硅烷氧基 Cope 重排的双功能产物 2 中通过伯胺的顺序亲核加成和随后的氢化以非常好的总产率和高立体选择性获得对映体纯哌啶 4。建议该反应通过初始亚胺形成然后分子内氮杂-共轭物加成到 α,β-不饱和酰亚胺来进行。立体选择性由亚胺 N-烷基和共轭双键之间的 A(1.2) 应变控制。在另一种方法中,多烷基取代的哌啶是通过将有机锌试剂添加到在银盐存在下容易从 Cope 产品中获得的氰基哌啶中制备的。