Gas-Phase Studies of Organic Reaction Mechanisms: Stereochemistry, Eliminations, and Catalytic Intermediates

这项研究将采用实验和计算技术相结合的方法来研究气相中的基本有机反应。虽然人们普遍认为气相方法可以为有机过程的机理提供重要的见解，但由于质谱学提供的三维结构信息有限，对反应立体化学的研究一直受到限制。在这项工作中，Gronert教授将通过使用同位素标记策略来确定消除和催化环丙烷化反应的立体化学偏好，从而克服这个问题。这两个过程在有机合成中都扮演着关键的角色，并且已经成为许多溶液研究的主题。在催化反应中，研究将利用质谱学的能力来分离和研究活性太强而无法在溶液中表征的模型中间体。这项工作的两个关键目标是(1)确定固有的(即，无溶剂的)反应偏好和(2)建立气相和溶液中的行为之间的相关性。这些信息对理解质谱学在新试剂和催化剂的开发中所起的作用至关重要。有了这个研究奖，有机和高分子化学计划支持弗吉尼亚联邦大学的斯科特·格罗内特的研究。格罗内特教授正在使用质谱仪研究气相中的有机反应。这种方法消除了与溶剂分子复杂的相互作用，并可以揭示控制反应过程的基本因素。质谱学数据将与计算模型的数据进行比较，并提供催化系统计算模型的可靠性信息。该项目的结果可用于开发新的、经济高效的方法，以快速评估潜在的有机合成催化剂的能力。学生的培训和参与融入了该项目，参与者将在现代仪器和化学技术方面获得宝贵的经验。

The research will employ a combination of experimental and computational techniques to study fundamental organic reactions in the gas phase. Although it is well accepted that gas-phase methods can provide important insights into the mechanisms of organic processes, investigations of reaction stereochemistry have been limited because mass spectrometry provides limited 3-dimensional structural information. In this work, Professor Gronert will overcome this problem by using isotopic-labeling strategies to identify the stereochemical preferences of elimination and catalytic cyclopropanation reactions. Both processes play pivotal roles in organic synthesis and have been the subject of numerous studies in solution. In the catalytic reactions, the studies will take advantage of the ability of mass spectrometry to isolate and study model intermediates that are too reactive to be characterized in solution. Two key goals in the work are (1) identifying intrinsic (i.e., solvent-free) reaction preferences and (2) establishing correlations between behavior in the gas-phase and solution. This information is critical for understanding the role that mass spectrometry can play in the development of new reagents and catalysts.With this Research Award, the Organic and Macromolecular Chemistry Program supports the research of Scott Gronert of Virginia Commonwealth University. Professor Gronert is using mass spectrometry to study organic reactions in the gas phase. This approach eliminates complicating interactions with solvent molecules and can reveal the fundamental factors that govern the course of the reaction process. The mass spectrometry data will be compared with those from computational modeling and provide information on the reliability of computational models in catalytic systems. The results from this project can be used in the development of new, cost-efficient methods for rapidly assessing the capabilities of potential catalysts for organic synthesis. Student training and involvement is integrated into the project and the participants will gain valuable experience with modern instrumentation and chemical techniques.