CAREER: Bridging Synthesis and Computational Chemistry to Parameterize Noncovalent Interactions in Asymmetric Catalysis

化学系化学催化计划和既定的促进竞争性研究计划(EPSCoR)共同支持南密西西比大学(USM)Julie A.Pigza教授的研究计划。Pigza研究小组正在研究新的催化剂，将石油和生物质原料转化为社会使用的重要化学品。改进后的催化剂满足了更广泛的社会对重要化学构件的需求，同时减少了环境浪费。这项研究正在使用计算方法来了解催化剂是如何工作的，以使它们能够改进和有用。为了实现这些目标，研究生和本科生正在进行这个项目的综合、机械和计算方面的工作。这丰富了密西西比州的跨学科研究培训。这项研究介绍了两种教育策略，以招募和留住STEM研究中代表不足的群体。第一个是社区学院桥梁项目，通过真实的研究体验、专业发展研讨会和同伴指导关系，支持STEM转学专业的学生过渡到USM。第二种机制是一门计算化学迷你课程，重点是利用USM现有的NSF资助的超级计算设施进行催化。与双功能氢键供体和受体有机催化剂形成碳-碳或碳-杂原子键已成为过渡金属催化的一种可行的替代方法。这些有机催化剂的一个主要优点是利用了现有官能团的天然反应性。这项研究通过结合化学合成和计算量子化学来研究催化剂和底物之间的非共价相互作用。这项研究的目标是更深入地了解模仿生物系统中发现的那些小分子编目体的设计。具体地说，利用密度泛函理论对芳香族pi-pi稳定催化剂和底物之间的相互作用进行了系统的研究，以对这些微妙的非共价相互作用的重要性进行参数化和排序。具体的目的是探索未被探索的键转化，例如：(I)无过渡金属的不对称烯丙基烷基化，(Ii)手性无环醚的生成，以及(Iii)双亲亚甲基亲核试剂的形成及其与pi键的加成。综合教育和研究部分用于在海湾南部地区培养一支多样化的STEM劳动力队伍，包括高中、本科生和研究生，重点是那些传统上不接触研究的学生，包括社区大学学生。这项工作还利用了NSF资助的大学内现有的超级计算设施。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。

The Division of Chemistry Chemical Catalysis Program and the Established Program to Stimulate Competitive Research (EPSCoR) jointly support the research program of Professor Julie A. Pigza at the University of Southern Mississippi (USM). The Pigza research group is investigating new catalysts to transform petroleum and biomass feedstocks into important chemicals used in society. The improved catalysts meet the broader societal needs for important chemical building blocks while reducing environmental waste. The investigation is using computational methods to understand how the catalysts work to enable their improvement and usefulness. To accomplish these goals, graduate and undergraduate students are carrying out the synthetic, mechanistic, and computational aspects of this project. This is enriching interdisciplinary research training in the state of Mississippi. This research introduces two educational strategies to recruit and retain underrepresented groups into STEM research. The first is a Community College Bridge Program that is supporting STEM transfer student majors in their transition to USM through an authentic research experience, professional development workshops, and peer mentoring relationships. The second mechanism is a computational chemistry mini-course with a focus on catalysis utilizing an existing NSF-funded supercomputing facility at USM. The formation of carbon-carbon or carbon-heteroatom bonds with bifunctional hydrogen bond donor and acceptor organocatalysts has emerged as a viable alternative to transition metal catalysis. A key benefit to these organocatalysts is the exploitation of the innate reactivity of existing functional groups. This research investigates the ensemble of noncovalent interactions between a catalyst and substrate by combining chemical synthesis and computational quantum chemistry. The goal of this research is a deeper fundamental understanding of small molecule catalophore design mimicking those found in biological systems. Specifically, the systematic investigation of aromatic pi-pi stabilizing interactions between the catalyst and substrate is pursued using density functional theory to parameterize and rank the importance of these subtle non-covalent interactions. The specific aims probe underexplored bond transformations such as: (i) a transition metal-free asymmetric allylic alkylation, (ii) the generation of chiral, acyclic ethers, and (iii) the formation of ambiphilic methine nucleophiles and their addition to pi-bonds. The integrated educational and research components serve to train a diverse STEM workforce of high school, undergraduate, and graduate students within the Gulf South region with a focus on those students traditionally not exposed to research including community college students. This work also takes advantage of an existing NSF-funded supercomputing facility within the University.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.