Post-Synthetic Modification of Macromolecules via Photoredox Catalysis

通过这一奖项，美国国家科学基金会化学部化学合成计划支持宾夕法尼亚大学化学系加里·A·莫兰德教授开发新的修饰大分子方法的研究。大分子是由大量原子组成的，这些原子被组织成构成块状的亚单位。生物学的例子包括蛋白质和酶(由氨基酸亚基组成)，以及DNA(由核苷酸亚基组成)。大分子的非天然例子包括用于光伏和晶体管材料的碳基纳米结构，以及用作催化剂和药物输送系统的金属-有机骨架。为了有效地创建用于各种应用的大分子材料，有必要在不干扰其核心结构的情况下对大分子进行修饰，并且这样做的方式是将添加的基团放置在沿着大分子主干的精确位置。莫兰德教授和他的研究小组正在设计一种方法，利用光作为唯一的能源来激活催化剂，这些催化剂可以用于选择性和高效地修饰生物分子、碳基纳米结构和金属有机骨架。这些项目通过与一批制药和农用化学品公司合作，加快创新，并在更可持续和对环境有利的条件下将商品推向市场，从而影响经济增长和生活质量。参与该项目的学生通过与工业合作伙伴的合作，接受培训并获得与工业相关的研究经验。正在开发新的光氧化还原工艺，使反应能够在合成后修饰各种重要的大分子。这些转化的大分子靶标包括生物分子、金属有机骨架和碳基纳米结构(石墨烯、碳纳米管和富勒烯)。这些努力的重点是使用光氧化还原催化和光氧化还原/过渡金属双重催化，使前所未有的转化可以在极其温和的条件下进行，从而以直接的方式提供获得改性材料的途径。因此，这项研究正在解锁几乎可以在这些材料上进行的无限范围的修饰，允许不同科学领域的从业者为任何可能设想的应用定制设计他们的目标分子的结构变体。正在开发的方案允许在室温下在几分钟到几个小时的时间内进行这些改造，从而使它们可以在任何实验室环境中使用。这项技术的实施正在对科学的各个领域产生重大影响，包括生物技术、能源研究和材料科学。合成项目的翻译性质也为下一代合成化学家提供了重要的培训经验。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。

With this award, the Chemical Synthesis Program of the NSF Division of Chemistry is supporting the research of Professor Gary A. Molander of the Department of Chemistry at the University of Pennsylvania to develop new ways to modify macromolecules. Macromolecules are made up of a large number of atoms that are organized into building block subunits. Biological examples include proteins and enzymes (made of amino acid subunits), and DNA (formed from nucleotide subunits). Non-natural examples of macromolecules include carbon-based nanostructures used in photovoltaics and transistor materials, as well as metal-organic frameworks used as catalysts and drug-delivery systems. To efficiently create macromolecular materials for a diverse range of applications, it is necessary to modify macromolecules without disturbing their core structure and to do so in a manner that places the added groups in precise locations along the macromolecular backbone. Professor Molander and his research group are designing ways to use light as the sole energy source to activate catalysts that can be used to modify biomolecules, carbon-based nanostructures, and metal organic frameworks selectively and efficiently. The projects impact economic growth and quality of life through collaboration with a cohort of pharmaceutical and agrochemical companies to speed innovation and bring goods to market under more sustainable and environmentally benign conditions. The students involved in the project are trained and provided with industry-relevant research experience through collaborations with industrial partners.New photoredox processes are being developed as enabling reactions to modify a variety of important macromolecules post-synthetically. The macromolecular targets for these transformations include biomolecules, metal-organic frameworks, and carbon-based nanostructures (graphene, carbon nanotubes, and fullerenes). The focus of these efforts centers on the use of photoredox catalysis and photoredox/transition metal dual catalysis to allow unprecedented transformations to be conducted under extremely mild conditions, providing access to modified materials in a straightforward manner. Thus, the research is unlocking a virtually unlimited range of modifications that can be made on these materials, allowing practitioners in diverse fields of science to custom-design structural variants of their target molecules for any applications that might be envisioned. The protocols being developed allow these transformations to be carried out at room temperature in a matter of minutes to hours, permitting them to be utilized in any laboratory setting. The implementation of this technology is providing a significant impact to diverse areas of science, including biotechnology, energy research, and material science. The translational nature of the synthetic project is also providing important training experiences to the next generation of synthetic chemists.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.