多重氢键诱导的超分子宏观手性的研究与应用探索

Developing artificial systems to mimic the emergence of chirality is of vital importance in better understanding the mysterious origin of natural homochirality, and guiding the design of advanced chiroptical materials. Due to the highly complicated competitive pathways, for multiple component organic systems, the emergence and manipulation of supramolecular chirality remain considerable challenging, which hinders the further developing of chiral composite materials. This project shall utilize biomimetic strategy, taking advantage of multiple hydrogen bonding between components, to tailor the supramolecular chirality in multiple component self-assembly systems, and attempt to prepare functional chiral soft materials. We will synthesis a series of melamine derivatives with polar core and apolar rims, which shall improve the formation of duplex hydrogen bonding with N-terminated aromatic amino acids, and self-assembling into 1D chiral micro/nanofibers. Multiple component self-assembly offsets the disadvantage of crystallization-induced self-assembly pathway of N-terminated aromatic amino acids, and endows great flexibility for the preparation of soft materials from small organic building blocks. This project will emphasis on the exploration of particular property and advantage among their analogues as well as the influence on supramolecular chirality. We shall positively study their application in asymmetric catalysis as catalyst or matrix. Ascribed to the presence of chiral amino acids and melamine residue, after coordinating noble metal ions, there would be rich chiral catalytic centers on the surface of nanofibers. We will also utilize melamine derivative to coassemble amino acids bearing energy transfer donor and acceptor respectively, to prepare tri-component assemblies to explore their application as CPL antenna materials.

利用自组装策略构建超分子手性体系对于揭示自然界手性的起源和制备手性功能材料有着重要的意义。然而对含有多组分有机构筑基元体系，由于自组装路径的高度复杂性，超分子手性的产生和调控存在着很大的挑战。这在一定程度上阻碍了手性复合材料的发展。本项目利用仿生策略，拟利用不同有机组分之间的多重氢键来调控自组装体系的超分子手性并制备手性软物质功能材料。拟合成一系列的三聚氰胺衍生物，使其具有外缘非极性内核极性的特点，这将促进其与N封端的芳基氨基酸产生配对二重氢键。氢键络合物进一步堆积成一维螺旋微纳米结构。多组分自组装将弥补芳基氨基酸在水相中易发生结晶诱导自组装的缺点，并赋予其在小分子软物质材料方面的制备上极大的灵活性。此项目将重点研究三聚氰胺衍生物相对于其他类似物的特殊性和优势以及三聚氰胺侧基对超分子手性征的影响。我们还将探索它们在不对称催化上和圆偏振光能量转移方面的应用。

多层次手性超分子组装的构筑以及对结构-功能关系的阐述是目前手性超分子化学的关键科学问题。围绕这两个核心问题，在该基金的支持下，建立了一种多组分手性正交共组装新策略，并揭示了超分子倾斜手性的普适性和构效关系。针对多组分复杂体系中自组装路径控制的难点，利用氢键和电荷转移等正交作用力，首次实现了三组分协同手性自组装并揭示了作用机制；利用组分之间的共组装来实现对超分子手性的精准控制，包括产生、转移、放大和调控等行为；提出模块化自组装的概念，利用模块组合控制溶液手性自组装行为；拓展了多组分手性自组装在天然化合物手性检测和制备光学活性材料方面的应用。揭示了芳基手性分子晶体中超分子倾斜手性的一般存在性，证明了超分子倾斜手性与手性光学的构效关系，使得手性光学性质可预测；利用多组分分级自组装实现了超分子倾斜手性向微纳米层次手性的转变。实现了多面体低聚倍半硅氧烷构筑纳米手性结构，为超大尺寸分子纳米球的手性组装和功能化提供了新的途径。探索了基于σ-hole的卤键在调控手性超分子结构和光学性质上的作用。