temperature under an N2 atmosphere. Addition of N-methylimidazole to the reaction mixture leads to an increase in the epoxide yield. A correlation between the Lewis acidity of the Mn(III) center as tuned by the substituents on the phenolate ligand, and the epoxide yield and product selectivity has been observed. The present complexes act as better chemoselective catalysts for epoxidation of cyclohexene
[Mn(L)Cl]类型的新的
锰(III)配合物家族,其中H 2 L为1,4-双(2-羟基-苄基)-1,4-二氮杂((H 2(L1)) ,1,4-双(2-羟基-4-甲基苄基)-1,4-二氮杂((H 2(
L2)),1,4-双(2-羟基-3,5-二甲基苄基)-1,4-已分离出二氮杂
庚烷(H 2(L3))和1,4-双(2-羟基-3,5-二叔丁基苄基)-1,4-二氮杂烷(H 2(L4))并进行了研究环氧化反应的催化剂。配合物1-4已使用元素分析,电子光谱和电
化学方法以及ESI-MS进行了表征。的单晶X射线结构1和3包含MNN 2 ö 2
氯发色团具有新颖方锥体协调的几何形状(τ:1,0.11; 3,0.00)。所有配合物在溶液中均具有扭曲的方锥配位几何形状,如在电子光谱中观察到的特征谱带所揭示的那样。已进行了时变密度泛函理论(TD-DFT)计算,以帮助指定配合物的电子吸收光谱带。Mn(III)/ Mn(II))1-4的氧化还原电势(E