Mechanistic Studies of Organic Reactivity

有机反应机理研究

• 批准号: 1761151
• 负责人: Jeehiun Lee
• 金额: $ 45万
• 依托单位: Rutgers University New Brunswick
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-01 至 2023-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1761151&HistoricalAwards=false
• 关键词: Mechanistic; Studies; Organic; Reactivity

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.

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、动力学和机制 B 项目提供的资金来探索催化机制。 具体重点是 N-杂环卡宾 (NHC) 催化的反应。 NHC 是新型有机物质，已被证明可以作为一系列重要化学反应的催化剂。人们对这些反应的机制知之甚少。在没有溶剂的情况下，使用质谱仪通过计算和实验研究反应。不存在溶剂可以揭示内在的反应性。 这些基础机制研究为本科生和研究生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检查 N-杂环卡宾 (NHC) 的性质和反应性 NHC 是一种多功能物质，可为过渡金属催化剂提供配体，并且本身就是催化剂。 NHC 催化“Umpolung”反应，引发极性反转；该提案的重点是羰基碳的极性反转。 此类反应具有很大的合成实用性，但其机理却知之甚少。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来大大提高该反应的整体效用。气相特别适合这项研究，因为可以确定溶剂的作用。 对这些 NHC 催化转化的机理理解有助于开发改进的催化剂。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Experimental and Computational Gas Phase Acidities of Conjugate Acids of Triazolylidene Carbenes: Rationalizing Subtle Electronic Effects.

• DOI: 10.1021/jacs.7b05229
• 发表时间: 2017-10-25
• 期刊: Journal of the American Chemical Society
• 影响因子: 15
• 作者: Niu Y;Wang N;Muñoz A;Xu J;Zeng H;Rovis T;Lee JK
• 通讯作者: Lee JK

Gas-Phase Deprotonation of Benzhydryl Cations: Carbene Basicity, Multiplicity, and Rearrangements

二苯甲基阳离子的气相去质子化：卡宾碱度、多重性和重排

• DOI: 10.1021/acs.joc.9b00496
• 发表时间: 2019
• 期刊: The Journal of Organic Chemistry
• 作者: Xu, Jiahui;Mieres-Perez, Joel;Sanchez-Garcia, Elsa;Lee, Jeehiun K.
• 通讯作者: Lee, Jeehiun K.

Kinetic hydricity of silane hydrides in the gas phase

硅烷氢化物在气相中的动力学水度

• DOI: 10.1039/c9sc02118c
• 发表时间: 2019
• 期刊: Chemical Science
• 影响因子: 8.4
• 作者: Xu, Jiahui;Krajewski, Allison E.;Niu, Yijie;Kiruba, G. S. M.;Lee, Jeehiun K.
• 通讯作者: Lee, Jeehiun K.