Catalytic asymmetric epoxidation of unfunctionalized olefins using chiral (salen)manganese(III) complexes
作者:Ryo Irie、Keiko Noda、Yoshio Ito、Naohide Matsumoto、Tsutomu Katsuki
DOI:10.1016/s0957-4166(00)86102-9
日期:——
Several kinds of chiral (salen)manganese(III) complexes (2 and 3) having chiral salicylaldehyde and chiral ethylenediamine moieties were prepared and used for catalytic asymmetric epoxidation of unfunctionalized olefins with iodosobenzene as a terminal oxidant. Catalysts 2 and 3 were found to show the characteristic substrate specificity for the enantiofacial selection of olefins, respectively. Furthermore
制备了具有手性水杨醛和手性乙二胺部分的几种手性(salen)锰(III)配合物(2和3),并将其用于碘代苯作为末端氧化剂对未官能化烯烃的催化不对称环氧化。发现催化剂2和3分别显示出用于烯烃的对面选择的特征性底物特异性。此外,发现向环氧化反应体系中添加供体配体如吡啶N-氧化物或2-甲基咪唑可改变对映选择性。结果,对于(E)-1-苯基丙烯(56%ee的,与图2c中的2-甲基咪唑的存在下),(ê)芪(48%ee的,与图3a),和二氢化萘(83%ee的,与图3a中的吡啶存在下Ñ -氧化物)。