Diamine Ligands for Asymmetric Catalysis: Facile Synthesis of C2-Symmetric Piperazines from Seebach’s Oxazolidinone
作者:Zbigniew Kałuża、Rafał Ćwiek、Mirosław Dygas、Przemysław Kalicki
DOI:10.1055/s-0034-1378341
日期:——
C 2 -Symmetrical hemiaminal ethers and diamines with a piperazine core were synthesized starting from Seebach’s oxazolidinone. The new methodology is based on the dimerization of α-amino aldehydes to bicyclic bishemiaminal ethers, followed by reduction to the corresponding diamines. Several enantiopure piperazine derivatives bearing either methyl or bulky groups including isopropyl and aryl at the
从Seebach's 恶唑烷酮开始合成具有哌嗪核心的C 2 -对称半胺醛醚和二胺。新方法基于将 α-氨基醛二聚化为双环双半胺醛醚,然后还原为相应的二胺。应用该方法获得了几种在桥头碳原子处带有甲基或大体积基团(包括异丙基和芳基)的对映纯哌嗪衍生物。在铜催化的内消旋 -1,2-二醇的不对称酰化中对新配体的初步筛选产生了有希望的结果(高达 92% ee)。