Redox-active biopyrrin pigments in supramolecular radical assemblies

在化学系的大分子，超分子和纳米化学计划和化学合成计划的共同支持下，Elisa Tomat和亚利桑那大学的同事将采用生物启发的颜料来合成具有高度可调的磁性和微物理特性的新型超分子组装体。 该项目旨在对由此产生的电子结构和性质有一个基本的了解，以告知未来超分子材料的设计，用于潜在的应用，如捕光设备，光催化系统和分子磁体。该项目将为本科生和研究生提供多学科培训，并通过全校范围的辅导计划和推广活动提供专业成长的机会。Tomat博士领导亚利桑那大学的化学发现项目，该项目为大学生与中学生讨论科学概念提供了一个框架，促进了对科学的追求，同时强调了各级科学传播的重要性。 本研究计划将氧化还原活性生物吡咯配体在一个多功能的超分子自由基组件的新类别。生物吡咯，如三吡咯烷二酮和二吡咯烷二酮，其特征在于生物存在的血红素代谢物的支架作为过渡金属络合物中基于离域配体的自由基的稳定平台。这些低聚吡咯框架还呈现可调的光谱和电化学特征，并在溶液和固态中参与非共价相互作用，如π堆积和氢键。这些多功能构件的合成操作预计将允许控制多中心自由基和氧化还原响应组件中的自旋-自旋相互作用。通过光谱学、电化学、晶体学和计算方法的研究，将为这些可调分子组装提供详细的多方面表征，并可能增强对如何设计、构建和操纵超分子自由基组装的基本理解。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

With the joint support of the Macromolecular, Supramolecular and Nanochemistry Program and the Chemical Synthesis Program in the Division of Chemistry, Elisa Tomat and coworkers at the University of Arizona will employ biologically inspired pigments to synthesize novel supramolecular assemblies with highly tunable magnetic and photophysical properties. This project aims to gain a fundamental understanding of the resulting electronic structures and properties to inform future design of supramolecular materials for potential applications such as in light-harvesting devices, photocatalytic systems, and molecular magnets. This project will offer multidisciplinary training to undergraduate and graduate students as well as opportunities for professional growth through university-wide mentoring programs and outreach activities. Dr. Tomat leads the Chemistry Discovery program at the University of Arizona, that provides a framework for college students to discuss scientific concepts with middle-school students, promoting the pursuit science while highlighting the importance of science communication at all levels. This research project will incorporate redox-active biopyrrin ligands in a versatile new class of supramolecular radical assemblies. Biopyrrins, such as tripyrrindiones and dipyrrindiones, feature the scaffolds of biologically occurring heme metabolites as stable platforms for delocalized ligand-based radicals in transition metal complexes. These oligopyrrolic frameworks also present tunable spectroscopic and electrochemical profiles and engage in non-covalent interactions, such as pi-stacking and hydrogen bonding, in solution and in the solid state. Synthetic manipulations of these multi-functional building blocks are expected to allow control of the spin-spin interactions in multi-centered radical and redox-responsive assemblies. Investigations by spectroscopic, electrochemical, crystallographic, and computational methods will provide for a detailed multifaceted characterization of these tunable molecular assemblies and likely enhance fundamental understanding of how to design, build and manipulate supramolecular radical assemblies.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.