四氮金属配合物仿生催化不对称氧化研究进展

非血红素四氮锰、铁配合物催化的不对称氧化反应是有机合成化学中的重要转化.这类催化剂通过模拟自然界中金属酶的结构与功能特点实现了高效的催化不对称氧化,成功地在产物分子中引入手性中心,从而构建出一类有潜在应用价值的化合物.在这些四氮配体的设计中, N,N’-二甲基-1,2-环己二胺、联吡咯和脯氨酸的衍生物是主要的二胺骨架,与吡啶、苯并咪唑侧基的不同组合可以制备出各种催化活性的仿生配合物.同时配体取代基的调整也会对不对称氧化反应产生巨大的影响.给电子基和大位阻羧酸效应显著提高了仿生催化不对称氧化反应的效率和对映选择性.我们综述了近年来非血红素锰、铁配合物催化不对称氧化反应的研究进展,主要包含N,N’-二甲基-1,2-环己二胺、联吡咯和脯氨酸的衍生物作为二胺骨架,吡啶和苯并咪唑作为侧基的四氮配合物的结构设计以及配体结构对不对称环氧化和C-H键氧化反应活性的影响,并对该领域的发展前景做出了展望.

Advances in Biomimetic Catalytic Asymmetric Oxidation Catalyzed by N4 Metal Complexes

The asymmetric oxidation reaction catalyzed by non-heme N4 manganese and iron complexes is an important transformation in synthetic organic chemistry. The catalysts successfully realize efficient catalytic asymmetric oxidation by mimicking the structural characteristics and functionality of metalloenzymes in nature. Chiral centers are created in organic compounds with potential applications. In the design of N4 ligands, N,N''-dimethyl-1,2-cyclohexanediamine, bipyrrole and proline derivatives are the main diamine skeletons. A series of biomimetic complexes with various catalytic activities are prepared via different combinations of diamines with pyridine and benzimidazole groups. At the same time, the changes of substituents on the N4 ligands also have a huge impact on asymmetric oxidation reactions. In addition, the effect of electron-donating groups on the pyridine and large sterically hindered carboxylic acids in the processs significantly improves the corresponding efficiency and selectivity of asymmetric oxidation by biomimetic model compounds. This paper mainly describes N4 complexes consisting of N,N''-dimethyl-1,2-cyclohexanediamine, bipyrrole and proline derivatives as chiral diamine backbones, with pyridine and benzimidazole as nitrogenous donors. We focus on the structural design of related compounds and the effect of structures on the reactivity of asymmetric epoxidation of olefins and oxidation of C-H bonds. Finally, the development prospects of this field are prospected.