Asymmetric Hydrogenation Catalyzed by (Achiral Base)bis(dimethylglyoximato)cobalt(II)-Chiral Cocatalyst System
作者:Seiji Takeuchi、Yoshiaki Ohgo
DOI:10.1246/bcsj.57.1920
日期:1984.7
group at α- or β-carbon were prepared, and an asymmetric hydrogenation of methyl 2-(acetylamino)acrylate and N,N′-dimethyl-5-benzylidenehydantoin catalyzed by achiral base-coordinated bis(dimethylglyoximato)cobalt(II)-chiral cocatalyst system was examined by using each of them as the cocatalyst. The enantiomeric excess of N,N′-dimethyl-5-benzylhydantoin reached 79.1% with (S)-N-[(R)-1-phenylethyl]
制备了在α-或β-碳上具有仲酰胺基团的手性叔胺,并在非手性碱配位双(二甲基乙醛肟)催化下对2-(乙酰氨基)丙烯酸甲酯和N,N'-二甲基-5-苄基乙内酰脲进行了不对称加氢反应。 )钴(II)-手性助催化剂体系通过使用它们中的每一个作为助催化剂来进行检查。以(S)-N-[(R)-1-苯乙基]-2-奎宁环甲酰胺为助催化剂,N,N'-二甲基-5-苄基乙内酰脲对映体过量达到79.1%。对于相同的助催化剂,两种底物之间的对映选择性存在显着差异。关于助催化剂和底物构象的讨论导致提出了手性识别过渡态的模型。