The first asymmetric epoxidation using a combination of achiral (salen)manganese(III) complex and chiral amine
作者:Takashi Hashihayata、Yoshio Ito、Tsutomu Katsuki
DOI:10.1016/s0040-4020(97)00633-9
日期:1997.7
system for asymmetric epoxidation was developed by using an achiral (salen)manganese(III) complex with chiral amine. Commercially available (-)-sparteine showed the highest asymmetric induction over the other chiral amines examined and addition of water to the reaction medium improved the induction up to 73% ee in the epoxidation of chromene derivative. Application of the system to the asymmetric oxidation
通过使用非手性(salen)锰(III)与手性胺的配合物,开发了一种新的不对称环氧化催化剂体系。市售的(-)-天冬氨酸在所研究的其他手性胺上显示出最高的不对称诱导,向反应介质中加水可提高色烯衍生物的环氧化反应的诱导率,最高可达73%ee。还检查了该系统在甲基苯硫醚不对称氧化为其亚砜中的应用(至多25%ee)。这些结果支持了我们的建议,即Salen配体的非平面和手性结构在通过(salen)锰(III)络合物选择烯烃的对映体中起重要作用。