Functional Networks of Molecular Capsules

根据Nitschke小组在自组装金属有机笼材料、超分子组装的光诱导转化和系统化学领域的经验，拟议的研究将调查金属有机笼在催化方面的潜在应用。金属有机笼的组合能力创造了预先组织的环境，在空间上限制活性物质，并在条件变化时可逆地组装/拆卸，类似于酶利用的那些操作反应动力学和为新催化模式提供机会。拟开展的研究目前分为两个子项目：1.研究方向；“金属有机胶囊的光控可逆相转移”；“自组装M4L6笼内光催化水活化”。在第一种方法中，极性笼和非极性笼，在不同的相中，由一个配体子组分不同，在没有光的情况下收敛到极性笼，而光的存在驱动两者之间的平衡途径，其平衡分布有利于非极性笼。在第二个子项目中，提出了一个开放的水溶性四面体笼，其内向的吡啶酮o给体原子可以容纳4个Mn（III）离子彼此接近。笼的顶点作为光氧化还原催化剂，在光和末端氧化剂的存在下连续氧化Mn簇。水，能够通过笼和/或结合到自由的锰配位位点，然后可能被氧化成双氧和质子，同时将锰团簇恢复到初始状态。

Drawing on experience in the Nitschke group in the areas of self-assembled metal-organic cage materials, light-induced transformations of supramolecular assemblies, and systems chemistry, the proposed research will investigate potential applications of metal-organic cages for catalysis. The combined abilities of metal-organic cages to create pre-organised environments, spatially confine reactive species, and to reversibly assemble/disassemble upon a change in conditions resemble those exploited by enzymes to manipulate reaction kinetics and provide opportunities for new modes of catalysis.The proposed research is currently divided into two sub-projects: 1. 'Light-controlled reversible phase transfer of metal-organic capsules', and 2. 'Photocatalytic water activation within a self-assembled M4L6 cage'.In the first, a polar and a non-polar cage, within separate phases and differing by one ligand subcomponent, converge to the polar cage in the absence of light, while the presence of light drives a pathway of equilibration between the two, whose equilibrium distribution favours the non-polar cage.In the second sub-project, an open, water-soluble tetrahedral cage is proposed whose inward-facing pyridone O-donor atoms may accommodate 4 Mn(III) ions in proximity to one another. The vertices of the cage serve as photoredox catalysts, successively oxidising the Mn cluster in the presence of light and a terminal oxidant. Water, capable of passing through the cage and/or binding to free Mn coordination sites may then be oxidised to dioxygen and protons, while returning the Mn cluster to its initial state.