Functional Metal-Ligand Assemblies: Reactivity, Self-sorting and Catalysis

人体使用大而复杂的分子，如酶（一种蛋白质）来控制许多细胞过程。化学家们努力用人工类似物模拟这些生物结构的复杂性，但这些模拟物无法接近天然酶的复杂性。自组装是一种强大的方法来创建大的，复杂的分子，而没有复杂的一步一步合成的挑战。这个过程类似于分子水平的乐高，单个的碎片可以简单地组合在一起，形成一个更大、更复杂的结构。在这个研究项目中，Hooley教授旨在开发自组装方法，以创建类似于酶的新化学结构，并探索这些结构在催化中的潜在应用。该项目为研究生提供跨学科的研究培训，并为未被充分代表的本科生提供智力和创造性发展的机会。教育创新与研究相结合，鼓励本科生和未被充分代表的少数民族从事科学事业，并改善加州大学河滨分校的化学课程，重点是提高STEM领域学生的保留率。自组装笼状配合物可以显示出新的材料和传感特性，但简单的分子多面体在其功能应用方面存在局限性。胡利教授的研究小组试图通过基于金属配体的自组装创造新的功能性合成受体来补救这一问题。本项目主要研究三个具体领域：1)利用配体内部功能控制笼状配合物的自组装过程（通过二级弱相互作用），包括自分选和控制笼状配合物的化学计量和立体化学；2)内部官能团的组装后修饰，以改变反应性，并允许在不同多面体几何形状和笼状配合物的捕获之间进行可控的、可逆的结构切换；3)这些配合物作为仿生催化剂在串联、正交催化中的应用。该领域的一个重要目标是证明在笼内的酸性和碱性功能的隔离使得通常不相容的反应可以在一个锅中进行。

The human body uses large, complex molecules such as enzymes (a type of protein) to control many cellular processes. Chemists strive to mimic the complexity of these biological structures with artificial analogs, but these mimics cannot approach the complexity of natural enzymes. Self-assembly is a powerful approach to create large, complex molecules without the challenge of complex step-by-step synthesis. This process is similar to molecular-level Lego, whereby individual pieces can be simply put together to make a larger, more complex structure. In this research project, Prof. Hooley aims to develop self-assembly approaches to creating new chemical structures that act in a manner similar to enzymes and to explore the potential applications of these structures in catalysis. This project provides interdisciplinary research training to graduate students and opportunities to underrepresented undergraduates for intellectual and creative development. Educational innovations are integrated with research to encourage undergraduates and underrepresented minorities to pursue careers in science and to improve the chemistry curriculum at UC Riverside with a focus on increasing retention of students in STEM fields. Self-assembled cage complexes can display novel material and sensing properties, but simple molecular polyhedra have limits in their functional applications. Prof. Hooley's research group seeks to remedy this by creating new functional synthetic receptors via metal-ligand based self-assembly. This project focuses on three specific areas: 1) the application of internal functions of ligands to control (via secondary weak interactions) the self-assembly process, including self-sorting and the control of stoichiometry and stereochemistry of cage complexes; 2) post-assembly modifications of internal functional groups to alter reactivity and to allow controlled, reversible structural switching between different polyhedral geometries and trapping of cage complexes; and 3) the application of these complexes as biomimetic catalysts in tandem, orthogonal catalysis. An important objective in this area is to demonstrate that the sequestration of acidic and basic functions in cage interiors allows normally incompatible reactions to be performed in a single pot.