Mechanistic Studies of Organic Reactivity

罗格斯大学化学系的Jeehiun Katherine Lee教授正在利用化学系化学结构、动态和机制B项目提供的资金来探索催化的机制。具体的重点将是n -杂环碳烯（NHCs）催化的反应。NHCs是一种新型有机物质，已被证明可作为多种重要化学反应的催化剂。人们对这些反应的机理了解甚少。在没有溶剂的情况下，用质谱仪对反应进行了计算和实验研究。溶剂的缺乏使本征反应性得以显露。这些基础的机械研究为本科生和研究生的科学家提供了教育机会。该项目还为科学界代表性不足的群体提供指导和培训。质谱和理论计算用于研究n -杂环碳烯（NHCs）的性质和反应性NHCs是一种多用途的物质，可以为过渡金属催化剂提供配体，也可以作为催化剂。NHCs催化“Umpolung”反应，引发极性反转；这一建议的重点是在一个羰基碳极性反转。这类反应具有很大的合成效用，但其机理尚不清楚。计算和实验都被用来探索极性反转发生的机制，并计划设计一种策略，以大大提高该反应的整体效用。气相是唯一适合于这项研究，因为溶剂的作用可以确定。对这些nhc催化转化机理的了解有助于改进催化剂的开发。该奖项反映了美国国家科学基金会的法定使命，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。

Professor Jeehiun Katherine Lee of the Department of Chemistry at Rutgers University is utilizing funding provided by the Chemical Structure, Dynamic & Mechanism B Program of the Chemistry Division to explore mechanisms of catalysis. The specific focus will be reactions catalyzed by N-heterocyclic carbenes (NHCs). NHCs are novel organic substances which have been shown to act as catalysts for a broad collection of important chemical reactions. Mechanisms for these reactions are poorly understood. Reactions are studied both computationally and experimentally, in the absence of solvent, using a mass spectrometer. The absence of solvent allows for intrinsic reactivity to be revealed. These fundamental mechanistic studies provide educational opportunities for undergraduate and graduate scientists. The project also provides mentoring and training for groups underrepresented in science. Mass spectrometric and theoretical computations are used to examine the properties and reactivities of N-heterocyclic carbenes (NHCs) NHCs are a versatile species that provide ligands for transition metal catalysts as well as being catalysts in their own right. NHCs catalyze "Umpolung" reactions, triggering polarity reversal; the focus of this proposal is on polarity reversal at a carbonyl carbon. Such reactions are of great synthetic utility, but the mechanism is poorly understood. Both computations and experiments are being used to probe the mechanisms by which the polarity reversal is incurred, with the plan of designing a strategy that would greatly enhance the overall utility of this reaction. The gas phase is uniquely suited to this study because the role of solvent can be ascertained. Mechanistic understanding of these NHC-catalyzed transformations leads to the development of improved catalysts.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.