Asymmetric Hydrogenation of Dehydrodipeptides with Rhodium(I)–Chiral Diphosphinites. Selective (<i>S</i>,<i>S</i>)- and (<i>R</i>,<i>R</i>)-Product Formation by Double Asymmetric Induction
作者:Masanobu Yatagai、Takamichi Yamagishi、Mitsuhiko Hida
DOI:10.1246/bcsj.57.823
日期:1984.3
stereoselectivities, depending on the chiral center of the substrates. This result was ascribed to the electrostatic interaction between the ligand and substrate. POP’s without ω-(dimethylamino)alkyl group gave (R,R)-product for (R)-substrate in a high stereoselectivity by the steric effect between the ligand and substrate, while for (S)-substrate, (S,S)-product was obtained in a low stereoselectivity.
在脱氢二肽的氢化中,使用含有吡咯烷部分的 Rh(I)-手性二亚膦酸盐 (POP) 的催化剂检查了底物 ((S) 或 (R)) 的手性中心对不对称诱导的影响。具有 ω-(二甲氨基) 烷基的 POP 的催化剂显示出极大的双不对称诱导,以高立体选择性产生 (S,S)- 或 (R,R)- 产物,具体取决于底物的手性中心。该结果归因于配体和底物之间的静电相互作用。没有ω-(二甲氨基)烷基的POPs通过配体和底物之间的空间效应以高立体选择性为(R)-底物提供(R,R)-产物,而对于(S)-底物,(S,S) -产物以低立体选择性获得。