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

人体使用酶(一种蛋白质)等复杂的大分子来控制许多细胞过程。化学家们努力用人造类似物来模拟这些生物结构的复杂性，但这些模拟物不能接近天然酶的复杂性。自组装是一种强大的方法来创造大的，复杂的分子，而不是复杂的一步一步的合成。这一过程类似于分子级别的乐高，只需将单个乐高碎片放在一起，就可以形成更大、更复杂的结构。在这项研究项目中，胡利教授的目标是开发自组装方法来创建以类似酶的方式工作的新的化学结构，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族裔在科学领域追求职业生涯，并改进加州大学河滨分校的化学课程，重点是增加STEM领域的学生留存率。自组装笼状化合物可以显示出新的材料和传感性能，但简单的分子多面体在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弥补这一点。该项目集中在三个具体领域：1)应用配体的内部功能来控制(通过次级弱相互作用)自组装过程，包括自分类以及笼状络合物的化学计量比和立体化学的控制；2)内部官能团的组装后修饰，以改变反应活性，并允许在不同多面体几何形状之间进行受控的可逆结构转换和笼状络合物的捕获；以及3)这些络合物作为仿生催化剂在串联、正交催化中的应用。这一领域的一个重要目标是证明笼子内部的酸性和碱性功能的隔离允许在单个锅中进行通常不相容的反应。

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.