CAREER: Bimolecular Mechanisms for Nickel-Mediated Bond Formation

过渡金属催化可以高效、经济地合成有机化合物，在化学、制药和聚合物制造中有着广泛的应用。与非常常用的贵金属催化剂相比，镍催化剂是一种廉价且地球资源丰富的替代品。此外，镍提供了新的化学反应和产品类型，以及前所未有的反应性。在这个项目中，刁天宁博士正在进行一项基础研究，以了解镍如何在有机化学中的重要元素之间形成化学键，从而为解决这类至关重要的化学反应中的实际挑战提供基础。​​​定义明确的双金属镍配合物经过氧化生成混合价和高价中间体，这些中间体迅速形成碳-碳、碳-卤素和氮-氮键。Ni-Ni键的光谱表征及其在稳定反应中间体中的作用为化学合成新反应的开发提供了机理基础。​​

Transition metal catalysis allows for the efficient and economical syntheses of organic compounds that finds widespread applications in chemical, pharmaceutical, and polymer manufacturing. In comparison to the very commonly used precious metal catalysts, catalysts based on nickel represent an inexpensive and earth-abundant alternative. In addition, nickel provides access to new types of chemical reactions and products, as well as unprecedented reactivity. In this project, Dr. Tianning Diao is conducting a fundamental study to understand how nickel forms chemical bonds between elements of importance in organic chemistry, thereby providing the basis for solving practical challenges in this critically important class of chemical reactions. In addition to training students at the interface of organic and inorganic chemistry, Dr. Diao is developing a summer workshop program to help teachers from institutions with underrepresented minority students overcome challenges in teaching science. In addition, Dr. Diao is actively engaged in creating, editing, and updating contents in ChemWiki, a free online textbook, serving students worldwide. With funding from the Chemical Catalysis Program of the Chemistry Division, Dr. Diao of New York University is establishing bimolecular reductive elimination mechanisms for a variety of Ni-mediated bond formation processes. Well-defined bimetallic Ni complexes undergo oxidation to generate mixed-valent and high-valent intermediates, which rapidly proceed to form carbon-carbon, carbon-halogen, and nitrogen-nitrogen bonds. Spectroscopic characterization of Ni-Ni bonds and their roles in stabilizing reactive intermediates provide the mechanistic basis for developing new reactions for chemical synthesis. Dr. Diao is actively contributing to Chemwiki, a free online textbook, serving students worldwide, especially the financially disadvantaged. In addition, Dr. Diao is developing a summer workshop program to help enhance teaching of science at institutions with underrepresented minority students.