Synthesis and activity of macrocyclized chiral Mn(III)–Schiff-base epoxidation catalysts
作者:Alexandre Martinez、Catherine Hemmert、Heinz Gornitzka、Bernard Meunier
DOI:10.1016/j.jorganchem.2005.01.055
日期:2005.4
A series of chiral macrocyclic Mn(III)Salen complexes has been prepared with two salicylidene moieties linked in their 3 and 3′ positions by aliphatic polyether bridges of variable lengths or by a more rigid aromatic junction arm. X-ray structures of ligand precursors and of complex 8 have been performed. All complexes have been used in the asymmetric epoxidation of 1,2-dihydronaphthalene with NaOCl
已经制备了一系列手性大环Mn(III)Salen配合物,其中两个水杨叉部分通过可变长度的脂族聚醚桥或更刚性的芳族连接臂在其3和3'位置连接。已经进行了配体前体和配合物8的X射线结构。所有的络合物都已用于NaOCl作为氧原子供体的1,2-二氢萘的不对称环氧化中,并显示出适度的对映体过量。选择配合物10用两种顺式-二取代的烯烃和几种氧化剂(即NaOCl,PhIO和n -Bu 4 NHSO 5)进行测试。当分别使用10和NaOCl和PhIO时,从2,2'-二甲基氧化烯获得ee值分别为56%和74%的2,2'-二甲基氧化烯。