CAREER: Small Molecule Redox Reactivity at MOF Secondary Building Units

该项目描述了一个职业规划，将氧化还原活性金属有机框架材料的小分子反应性的基础研究与互动无机化学课程材料的创建结合起来，为全球数百万学生提供，并努力增加波士顿市中心学校高中学生的大学申请。本项目合成和研究的材料和小分子底物代表了世界范围内关注的大型新兴材料，即金属有机框架（mof）和与生物和化学工业相关的小分子。技术摘要本研究解决了自然和合成化学家在利用与生物和工业催化相关的小分子方面的明显脱节。虽然生命系统使用复杂的超分子结构，其中多种因素——折叠、活性位点环境、次级球体相互作用——有助于底物的选择性和整体反应性，但使用小分子作为底物的金属配合物通常依赖于几乎完全集中在初级配位球体上的配体设计，并且往往缺乏自然界中所见的功能。研究小组已经证明，微孔mof在模拟自然系统的配体场环境中支持高度还原的第一行过渡金属离子。这些离子与小分子氧化剂相互作用的方式也让人想起生物和工业催化循环中涉及的活性中间体。该团队的工作强调了这些材料作为异质材料的独特作用，通过填补金属酶和多孔异质材料（如沸石）之间的重要缺失环节。该项目主要致力于合成具有氧化还原活性的新型多孔材料，这些材料能够吸引小分子进行进一步的反应性，主要研究三个方向：(1)具有高氧化还原活性和还原金属离子的mof的合成和表征，包括许多尚未在此类材料中分离出来的金属离子；(2)探索新框架的氧化还原反应性，特别关注小型工业相关的气态氧化剂，如双氧和卤素；(3)开发新的可预测的软合成方法，用于生产具有氧化还原活性金属中心的mof，并为mof中的小分子氧化还原化学提供新的合成工具箱。

Non-technical abstractThis project describes a career plan that integrates fundamental studies of small molecule reactivity at redox-active metal-organic framework materials with the creation of interactive inorganic chemistry course materials to be made available to millions of students worldwide and with efforts to increase college applications from high school students in inner-city Boston schools. The materials and small molecule substrates synthesized and studied in this project are representative of large classes of emerging materials of worldwide interest known as metal-organic frameworks (MOFs) and of small molecules relevant in both biology and the chemical industry. Technical abstractThis research addresses the apparent disconnect between the ways Nature and synthetic chemists approach the utilization of small molecules of relevance to biological and industrial catalysis. While living systems use complex supramolecular architectures where multiple factors - folding, active site environment, secondary sphere interactions - contribute to substrate selectivity and overall reactivity, metal complexes that use small molecules as substrates typically rely on ligand design that focuses almost entirely on the primary coordination sphere, and often fall short of the functionality seen in Nature. The research team has shown that microporous MOFs support highly reduced first row transition metal ions in ligand field environments that mimic those found in natural systems. These ions interact with small molecule oxidants in ways that are also reminiscent of reactive intermediates involved in both biological and industrial catalytic cycles. The team's work highlights the unique role that these materials could play as heterogeneous materials by filling an important missing link between metalloenzymes and porous heterogeneous materials such as zeolites. The project focuses on synthesizing new redox-active porous materials capable of engaging small molecules for further reactivity, pursing three main directions: (1) The synthesis and characterization of MOFs with highly redox-active and reduced metal ions, including many that have not yet been isolated within such materials; (2) Exploration of the redox reactivity of the new frameworks, focusing in particular on small, industrially relevant gaseous oxidants such as dioxygen and the halogens; (3) Developing new and predictable soft synthetic methodologies for producing MOFs with redox-active metal centers and a new synthetic toolbox for small molecule redox chemistry in MOFs.