三齿希夫碱类手性金属-有机框架的设计合成及异相不对称催化性能

Chiral metal-organic frameworks have become one of the hot topics of chemistry in recent years due to their potential applications in heterogeneous asymmetric catalysis，chiral sensing and chiral recognition and resolution. In this project, a variety of chiral bridging ligands bearing different sizes, binding abilities, and electronic and stereo configurations will be designed and synthesized based on the chiral tridentate Schiff-base skeletons. A series of novel homochiral metal-organic porous materials featuring diverse structures and functionalities will then be constructed based on the principles of coordination and supramolecular chemistry, with the structures fully characterized and related physical properties studied in details. The controllable synthesis and highly efficient preparation could be achieved by exploring the impact of the electronic and spatial structures of chiral ligands, inorganic building blocks as well as synthetic methods on the resulted structures and properties of the materials. Besides, the research will be focused on studying the asymmetric catalytic properties of MOFs in heterogeneous processes. Therefore, substrates with different sizes and structures will be judiciously selected to explore the activity, selectivity, recyclability and mechanism of chiral frameworks-based catalysts. Direct fuctionalization of chiral bridging ligands and postsynthetic modification of the as-synthesized frameworks will also be employed for delicate adjustment of the pores and surfaces of MOFs, thus enhancing the fuctions and catalytic performances. The project will provide scientific support and research basis for the development of crystalline chiral frameworks-based catalysts with practical applications as well as further promotion of chiral science and technology.

鉴于在异相不对称催化、手性传感、手性识别与分离等方面的潜在应用价值, 近年来手性金属-有机框架已成为化学领域的研究热点之一。本项目拟以具有光学活性的三齿希夫碱为平台，设计合成尺寸、配位能力、电子和立体结构不同的手性桥联配体，根据配位化学和超分子化学的原理构筑系列结构和功能各异的手性金属-有机多孔材料，并对材料的结构和相关物理性能进行表征和研究，探索手性配体的电子和立体结构、无机组分、制备方法等对材料结构和性能的影响，进而实现材料的可控合成和有效制备。重点研究材料的异相不对称催化性能，通过选定尺寸和结构不同的底物考察催化剂的活性、选择性、循环使用性和反应机理，并利用修饰手性配体或后修饰材料结构等手段调控催化剂孔道微环境和表面特性，实现催化剂功能的增强和复合。本项目研究工作的开展将为研制具有应用前景的手性金属-有机框架催化剂以及发展手性科学和技术提供科学依据和研究基础。

金属-有机框架材料是一类新型的多功能晶态材料，近年来在气体吸附、传感、催化与分离等领域展示出良好的应用潜力。和无机沸石类材料相比，由于多孔金属-有机框架材料的结构和性能具有易于设计和调控的优点，因此将其作为异相催化剂的研究成为各国化学家的近年来的研究热点。本项目主要以ONO三齿希夫碱、V形桥联配体、8-羟基喹啉以及氨基酸类化合物为骨架，设计合成了多种电子、立体结构和功能不同的桥联配体；利用配位化学、超分子原理和晶体工程的方法，构建了系列具有不同结构的金属-有机材料，并通过XRD、TGA等技术手段表征了材料的结构及相关物理化学性质；根据所制备材料的结构特点和孔性质，深入研究了合成材料的异相催化性能，特别是选定了不同尺寸的底物考察了催化剂的活性、普适性、选择性以及循环使用性能；此外，通过深入研究考察了催化剂的晶体结构、组成成分和催化性能之间的关系，揭示了此类催化剂微观结构环境对其催化性能的主要影响，这有助于进一步获得催化功能增强型金属-有机框架催化剂。通过本项目的研究为将来指导和合成具有应用前景的新型晶态金属-有机材料奠定了研究基础。