Gas-Phase Studies of Charged Aromatic Radicals and Biradicals

带电芳香自由基和双自由基的气相研究

• 批准号: 0078924
• 负责人: Hilkka Kenttamaa
• 金额: $ 32.8万
• 依托单位: Purdue Research Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-15 至 2003-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0078924&HistoricalAwards=false
• 关键词: Gas; Phase; Studies; Charged; Aromatic

With this renewal award the Organic and Macromolecular Chemistry Program supports the work of Dr. Hilkka I. Kenttamaa of the Department of Chemistry at Purdue University in West Lafayette, Indiana. The purpose of this work is to generate aromatic biradicals (1,n-arynes) in the gas phase, and study their product branching ratios and rate constants in reactions with atom donors, electophiles, nucleophiles, and stable radicals. Each biradical carries a chemically inert charged substituent that allows it and its reaction products to be studied by Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR). Structural features of the biradicals will be varied, including the distance and orientation of the two radical sigma-orbital lobes, the type of charged group, and the presence of additional substituents. Reactivity-controlling parameters to be investigated include the biradicals' singlet-triplet gaps and the polarity of their transition states. Experimental studies will be complemented by molecular orbital calculations.The proposed research is at the frontiers of mass spectrometry in studies of short-lived reaction intermediates. The fundamental information to be obtained is likely to be of great interest to organic and organometallic chemists who use radicals and biradicals in synthesis. The PI has a large group of undergraduate and graduate students, about half of whom are female or from underrepresented groups. For them the research is expected to provide a valuable educational experience.

通过这一续签奖项，有机和高分子化学项目支持印第安纳州西拉斐特普渡大学化学系的 Hilkka I. Kenttamaa 博士的工作。 这项工作的目的是在气相中生成芳香族双自由基（1,n-芳炔），并研究其与原子供体、亲电体、亲核体和稳定自由基反应时的产物支化比和速率常数。 每个双自由基都带有一个化学惰性带电取代基，使其及其反应产物可以通过傅里叶变换离子回旋共振质谱（FT-ICR）进行研究。 双自由基的结构特征会有所不同，包括两个自由基西格玛轨道瓣的距离和方向、带电基团的类型以及其他取代基的存在。 要研究的反应性控制参数包括双自由基的单线态-三线态间隙及其过渡态的极性。 实验研究将得到分子轨道计算的补充。这项研究处于短寿命反应中间体质谱研究的前沿。 在合成中使用自由基和双自由基的有机和有机金属化学家可能会对所获得的基本信息非常感兴趣。 PI 拥有大量本科生和研究生，其中约一半是女性或来自代表性不足的群体。 对于他们来说，这项研究有望提供宝贵的教育经验。