Electrostatic Regulation of Cavity-Mediated Catalysis

催化是一种过程，在这个过程中，少量的物质(催化剂)可以加快所需的化学反应的速度。催化在许多工业应用中起着至关重要的作用。制造有价值的产品，如药品、塑料、农用化学品和清洁燃料，往往需要适当设计的催化剂。传统的催化剂在促进广泛的化学反应方面非常有效。然而，制造仿效酶的卓越性能的催化剂仍然是一项艰巨的任务，而酶是大自然的催化剂。挑战在很大程度上源于构建类似酶的复杂分子的困难。在这个项目中，南达科他大学的王振强博士正在应用几种生物学原理来合成模拟酶的新型分子。这项研究与针对美洲原住民学生的教育推广计划相结合，以促进STEM(科学、技术、工程和数学)教育。这些项目正在通过王博士的实验室主持的部落师生研究团队以及地区部落学院的化学研讨会来吸引当地部落大学生。外展还包括现场接待来自当地主要本科院校(PUI)的学生，以及为本国机构的师生研究团队提供“在家”支持。在这个由化学系化学催化项目资助的项目中，南达科他州大学的王博士领导的团队正在利用一种独特的合成受体类别，即金属-有机超级容器(MOSC)，来研究催化的新概念。基于MoC的超分子催化剂在结构上是独特的，因为它们是由容器-分子前体(即磺酰杯芳烃)构建的，并且具有多个纳米腔作为底物结合部位。MoC催化剂还具有多功能的金属结合H2O物种，可以促进氢键、Bronsted酸、Bronsted碱和级联催化。采用多功能纳米空腔和静电调节两种关键策略来提高催化效率、提高反应选择性和调节超分子反应活性。MOSCs独特的结构特征，包括组成的多功能性、结构的模块化和多孔结构，使它们有别于其他合成的受体分子，为催化活性中心的功能化和工程超分子反应性提供了前所未有的机会。使用离子物种作为静电调节剂来调节超分子催化的策略，本身就是催化惰性的，与依赖于包裹催化活性物种的传统方法在概念上是不同的。静电调节的概念尚未得到化学家的完全认可，但它不仅有可能显著扩大可接触反应的范围，而且有可能从根本上改变超分子催化的设计方式。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Catalysis is a process in which a small amount of a substance (a catalyst) accelerates the rate of desirable chemical reactions. Catalysis plays a vital role in many industrial applications. Manufacturing valuable products such as pharmaceuticals, plastics, agrochemicals, and clean fuels often requires properly designed catalysts. Traditional catalysts are highly effective in promoting a wide range of chemical reactions. However, it remains a daunting task to make catalysts that emulate the remarkable performance of enzymes, which are Nature's catalysts. The challenge arises largely from the difficulty of constructing molecules that resemble the complexity of enzymes. In this project, Dr. Zhenqiang Wang of the University of South Dakota is applying several biology-inspired principles to synthesize new classes of molecules that mimic enzymes. This research is integrated with educational outreach programs targeting Native American students to promote STEM (science, technology, engineering, and mathematics) education. These programs are engaging local tribal college students through tribal student-faculty research teams hosted in Dr. Wang's laboratory and through chemistry workshops at regional tribal colleges. The outreach also includes onsite hosting of students from local primarily undergraduate institutions (PUIs) and "at-home" support for student-faculty research teams at their home institutions.In this project funded by the Chemical Catalysis program of the Chemistry Division, the team led by Dr. Wang at the University of South Dakota is utilizing a unique class of synthetic receptors, known as metal-organic supercontainers (MOSCs), to investigate new concepts of catalysis. The MOSC-based supramolecular catalysts are structurally unique in that they are constructed from container-molecule precursors (i.e., sulfonylcalixarenes) and feature multiple nano-cavities that serve as substrate binding sites. The MOSC catalysts also feature functionally versatile metal-bound H2O species, which may promote hydrogen-bond, Bronsted-acid, Bronsted-base, and cascade catalysis. Two key strategies, namely, multifunctional nano-cavities and electrostatic regulation, are used to promote the catalytic efficacy, enhance reaction selectivity, and regulate supramolecular reactivity. The unique structural characteristics of the MOSCs, including their compositional versatility, structural modularity, and multi-pore architecture, distinguish them from other synthetic receptor molecules and provide unprecedented opportunities for functionalizing catalytic active sites and engineering supramolecular reactivity. The strategy to modulate supramolecular catalysis using ionic species as electrostatic regulators, which are catalytically inert on their own, is conceptually distinct from conventional methods that rely on encapsulating catalytically active species. The concept of electrostatic regulation is not yet fully recognized by chemists, but has the potential to not only significantly expand the scope of accessible reactions, but fundamentally transform how supramolecular catalysis can be designed.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.