Theory and Design of Transition-Metal Heterodinuclear and Homodinuclear Catalytic Reactions

开发新的催化剂是发现新的化学反应的关键。传统上，分子催化剂使用一个金属原子。具有双金属原子(双核)的催化剂具有新的反应性，特别是对于许多经典的单金属策略尚未解决的具有挑战性的化学反应。目前，科学家们还不完全了解双核催化剂是如何运作的，也不知道如何改进它们。在这个项目中，杨百翰大学的Daniel Ess博士正在使用计算方法来理解双核金属-金属相互作用的机制和发展一般原理。这项工作与实验合作紧密结合，正在导致新催化剂和化学反应的发现。这项工作还为研究生和本科生提供了化学和计算机科学相结合的科学培训。Ess博士参与了与这项研究相关的几项外展活动。例如，Ess博士每年在杨百翰大学为100多名9-14岁的儿童和青年主持夏季化学夏令营，参加人数较少的群体。在化学系化学催化项目的资助下，杨百翰大学的Ess博士正在使用计算化学方法来加深对过渡金属异双核和同双核催化的理解。所研究的催化剂在两种过渡金属或一种过渡金属和主族金属之间具有单一的共价键或直接的配位/静电相互作用。目前正在研究用于碳-碳偶联、烯烃加氢和芳烃胺化等反应的钴-锆、钚-银、镍和镝催化剂的反应机理。通过比较双核催化剂和单核催化剂以及金属-金属配对的影响，正在制定双核催化剂的反应性和选择性原理，用于乙烯聚合和二烯氢芳基化等反应的Ru-Zr、Ru-Ag、Rh-Li和Ni-Na催化剂。这项工作还利用计算方法设计了用于芳烃硼化和手性烯丙基胺化的新型异双核催化剂。本科生和研究生正在接受现代计算技术的培训，其中包括使用和开发用于自旋交叉反应和直接动力学的软件。学生们与实验小组互动，学习如何将计算化学与实验相结合。Ess博士利用杨百翰大学的本科生实验室为100多名9-14岁的儿童和青年主持了一个化学和生物化学夏季夏令营，参加人数较少的群体。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。

Developing new catalysts is essential to discovering new chemical reactions. Traditionally, molecular catalysts use one metal atom. Catalysts with two metal atoms (dinuclear) have significant promise for new reactivity, especially for many challenging chemical reactions not yet solved by the classic one metal strategy. Currently, scientists do not completely understand how dinuclear catalysts operate, or how they can be improved. In this project Dr. Daniel Ess of Brigham Young University is using computational methods to understand mechanisms and develop general principles of dinuclear metal-metal interactions. This work, combined tightly with experimental collaboration, is leading to the discovery of new catalysts and chemical reactions. This work also provides scientific training at the interface of chemistry and computer science for graduate and undergraduate students. Dr. Ess is engaged in several outreach activities related to this research. For example, each year Dr. Ess directs a summer chemistry camp at BYU for more than 100 children and youth ages 9-14 with significant participation from underrepresented groups.With funding from the Chemical Catalysis Program of the Chemistry Division, Dr. Ess of Brigham Young University is using computational chemistry methods to develop understanding of transition-metal heterodinuclear and homodinuclear catalysis. Catalysts being investigated have a single covalent bond or direct dative/electrostatic interaction between two transition metals or a transition metal and main-group metal. Reaction mechanisms are being investigated for cobalt-zirconium, ruthenium-silver, dinickel, and dirhodium catalysts used in reactions such as carbon-carbon couplings, alkyne hydrogenation, and arene amination. Dinuclear catalyst principles of reactivity and selectivity are being developed by comparing dinuclear versus mononuclear catalysts, and the impact of metal-metal pairing, for ruthenium-zirconium, ruthenium-silver, rhodium-lithium, and nickel-sodium catalysts for reactions such as ethylene polymerization and diene hydroarylation. This work is also using computational methods to design new heterodinuclear catalysts for arene borylation and chiral allylic amination. Undergraduate and graduate students are being trained in modern computational techniques that include using and developing software for spin crossover reactions and direct dynamics. Students interact with experimental groups and are learning how to interface computational chemistry with experiment. Dr. Ess directs a summer chemistry and biochemistry camp using undergraduate labs at BYU for more than 100 children and youth ages 9-14 with significant participation from underrepresented groups.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.