【作者】 焦扬；

【导师】 段春迎； 何成；

【作者基本信息】 大连理工大学 ， 无机化学， 2013， 博士

【摘要】 生命体系中的一系列生命过程,都是通过一系列识别与催化过程完成的。金属有机多面体(MOPs),是由具有特定配位构型的金属离子与特定结构的配体经由配位自组装形成的结构高度有序的实体。金属有机多面体具有独特的结构,特定的空腔尺寸,在空腔内引入功能化的识别与催化位点,可以通过超分子作用识别客体分子,并且进行具有酶促动力学特征的催化反应。1.金属有机多面体对生物小分子的识别本文设计合成了富含三十六个酰胺基团的四臂配体,通过与稀土金属离子Ce3+配位自组装得到的变形三棱柱Ce-L1,利用其中含有十二个未参与配位的酰胺基团作为多重的氢键识别位点,通过笼状配合物的立体选择性的协同作用,可以在一系列天然糖类分子中选择性识别乳糖分子。设计合成的四面体配合物Zn-L2、Co-L2,能够选择性识别ATP分子。配合物分子中三苯胺基团的荧光特性,实现了在核糖核苷酸分子中以荧光为信号输出基团选择性识别ATP分子。2.金属有机多面体催化性能的研究设计合成了两种三臂配体,与稀土金属离子Ce3+配位自组装得到的变形四面体笼状配合物Ce-L3、Ce-L4,可以识别4-硝基苯甲醛分子。将其应用于醛类分子的硅腈化反应,实现了以变形四面体为分子反应器催化小的醛类分子的硅腈化反应。而四面体Ce-L5含有酰胺基团和大的共轭平面,以荧光和核磁为输出信号选择性识别9-蒽乙醛分子。同时作为分子反应器,以大的π-π堆积作用位点,实现了在提供反应环境的同时作为催化剂催化9-蒽乙醛分子的光二聚反应,生成[4,4]的光二聚环加成产物。跟踪9-蒽乙醛分子的硅腈化反应,在高浓度下反应呈现零级反应特征,反应进程可以被抑制剂抑制,表明四面体Ce-L5对9-蒽乙醛的催化过程具有酶促反应动力学特征。3.超分子光化学的研究吡啶钌的配合物与多酸组装成的超分子体系,光照条件下存在电子转移现象,并且组装的超分子体系光电稳定性和强度明显优于单一的体系,实现了超分子体系对光电信号传递的促进。以荧光素作为光敏剂,三乙胺为电子牺牲剂的光解水制氢体系中,笼状配合物Co-L7与光敏剂荧光素之间存在明显的主客体超分子作用,光解水制氢量明显高于相应基于单核钴的配合物Co-L8的反应体系,表明超分子作用在光解水制氢的过程中起到重要的促进作用,实现了通过超分子作用增强体系的光解水制氢产率。更多还原

【Abstract】 Biochemical reactions, which are necessary for all life processin living systems, undergo a series of recognition and catalytic process. Metal organic polyhedra (MOPs) are a kind of highly ordered entity which are self-assembled by the metal ions with a specific coordination geometry and the ligands. MOPs have unique structure and the cavity of the particular size. By introducing the catalytic and recognition sites in their cavity, MOPs could recognize guest molecules through supramolecular interaction and catalyze reactions mimicking enzymes.1The recognition of biological molecules based on metal-organic polyhedraThe octa-nuclear bicoronal triangular prism Ce-L1could be self-assembled by the four-arms ligands of thirty-six amide group and Ce3+. It could high selectively recognize lactose among related natural mono-and disaccharides solution through multiple hydrogen bonding sites of twelve amide bond groups and size selection. Tetrahedral complexes of Zn-L2, Co-L2were designed and synthesized to recognize ATP. The tetrahedral complexes worked as fluorescence sensors to selectively recognize ATP among ribonucleotide molecules based on fluorescence characteristics of triphenyl amine groups.2Studies on organic reactions catalyzed by metal-organic polyhedraThe Cerium-based warped tetrahedral structures Ce-L3and Ce-L4self-assembled from two ligands and Ce3+were designed and synthesized. They could recognize4-nitrobenzaldehyde and worked as molecular flasks to catalyze cyanosilylation reactions of aldehyde molecules. The tetrahedron Ce-L5containing amide groups and large conjugate planes could recognize2-(anthracen-9-yl)acetaldehyde accompany with signal output of the fluorescent and NMR. It worked as a molecular flask to catalyze photodimerization reactions of9-anthracene acetaldehyde through π-π interaction and get [4,4] cyclo-dimerization product. The cyanosilylation reactions were tracked by NMR which showed pseudo-zeroth-order characteristics at high concentration, and the reaction process could be inhibited by a inhibitor. It is suggested that the catalytic process worked as enzyme kinetics.3Studies on supramolecular photochemistryThe supramolecular systems containing polypyridyl ruthenium complexes and polyoxometalates have stable electrochemical and optoelectronic signals under photoreation, and the assembled supramolecular systems are morestable and stronger than a single system to achieve supramolecular systems for promotion of electrochemical and optoelectronic signals. In the hydrogen production system where fluorescein worked as a photosensitizer and triethylamine as an electron sacrificial agent, tetrahedral complexes Co-L7exhibited host-guest supramolecular interaction with photosensitizer fluorescein. The evolution of hydrogen production is significantly higher than the reaction system with corresponding cobalt-based mononuclear complexes Co-L8. It is suggested that the supramolecular interactions play an important role in light-driven the hydrogen production system and realized the promoting of hydrogen production through supramolecular interaction.更多还原