Metalloradical Catalysis for Selective Radical Reactions

有了这个奖项，NSF化学部的化学催化项目正在支持波士顿学院的Peter Zhang教授的研究。张教授正在开发新的金属络合物作为有机化合物合成的催化剂。大多数金属催化过程依赖于化学家所说的“极性反应”，即反应涉及一次转移或共享两个电子。张教授开发了“金属自由基催化”，其中反应涉及一次仅转移或共享一个电子。 张教授的新催化体系利用了这种自由基反应的独特特征。与催化双电子极性反应通常需要稀有和昂贵的金属离子相比，单电子金属自由基反应用基于地球上丰富和廉价的过渡金属如钴的催化剂进行。因此，这项研究正在解决精细化学品制造以及生物学，医学和材料应用中的可持续性问题。张教授还通过为K-12教师提供教育资源和激发K-12学生的科学兴趣，向公众推广科学。除了为研究生和博士后研究人员提供科学培训外，张教授的实验室还为高中生和教师以及本科生提供第一手的研究经验。张教授的研究中心是建立金属自由基催化作为一种全新的控制自由基反应的反应性和立体选择性的方法。金属自由基体系的基础上，钴（II）配合物的手性卟啉正在开发利用的全部潜力的均裂自由基化学。这些新的催化自由基过程，这是机械上独特的和操作上有吸引力的，作为宝贵的合成工具，用于构建有机化合物，包括生物重要的天然产物和药学上感兴趣的小分子。金属自由基催化的概念旨在充分探索均裂作为键断裂和键形成的基本途径，它对有机合成产生了深远的影响，并促进了基于自由基化学的新合成方法的发展。基于钴的金属自由基催化的成功展示促进了基于开壳金属离子和手性配体的不同组合的新的金属自由基催化剂体系的鉴定，其可以催化广泛的立体选择性自由基反应。虽然这项研究的重点是可推广的合成方法，合成目标的应用，包括第三组代谢型谷氨酸受体激动剂的目标可能会影响大脑的适当神经元功能。 此外，张教授正在创作名为“生活的色彩”的公共教育材料，提供给当地K-12学校的学生。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值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 Catalysis Program of the NSF Division of Chemistry is supporting the research of Professor Peter Zhang of Boston College. Professor Zhang is developing new metal complexes as catalysts for the synthesis of organic compounds. Most metal-catalyzed processes rely on what chemists call "polar reactivity" where reactions involve transfers or sharing of two electrons at a time. Professor Zhang develops "metalloradical catalysis" where reactions involve the transfer or sharing of only one electron at a time. Professor Zhang's new catalytic systems take advantage of the unique features of such radical reactions. In comparison with the typical need for rare and expensive metal ions for catalyzing two-electron polar reactions, the one-electron metalloradical reactions are carried out with catalysts based on earth-abundant and inexpensive transition metals such as cobalt. As such, this research is addressing important issues of sustainability in fine chemical manufacturing, and applications to biology, medicine, and materials. Professor Zhang is also promoting science among the general public by providing educational resources for K-12 teachers and stimulating scientific interests of K-12 students. In addition to scientific training for graduate students and postdoctoral researchers, Professor Zhang's laboratory provides first-hand research experiences to high school students and teachers as well as undergraduate students.Professor Zhang's research centers on establishing metalloradical catalysis as a fundamentally new approach for controlling reactivity and stereoselectivity of radical reactions. Metalloradical systems based on cobalt(II) complexes of chiral porphyrins are being developed to harness the full potential of homolytic radical chemistry. These new catalytic radical processes, which are both mechanistically distinctive and operationally attractive, are serving as valuable synthetic tools for the construction of organic compounds including biologically-important natural products and pharmaceutically-interesting small molecules. The concept of metalloradical catalysis, which aims at the full exploration of homolysis as a fundamental way for bond breaking and making, is having far-reaching impact on organic synthesis and is stimulating the development of new synthetic methods based on radical chemistry. The successful demonstration of cobalt-based metalloradical catalysis is prompting the identification of new metalloradical catalyst systems based on different combinations of open-shell metal ions and chiral ligands that can catalyze a broad range of stereoselective radical reactions. While this research focuses on generalizable synthetic methods, applications to synthetic targets, including targets that are group III metabotropic glutamate receptor agonists may have implications in the proper neuronal function of the brain. In addition, Professor Zhang is creating public educational materials entitled "The Colors of Life" presented to students in local K-12 schools. These educational materials are being made available for public access in PowerPoint format via the web.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.