Pushing the Limits of Reactivity Principles for Organic Reactions

在这个由化学部化学结构、动力学和机理B （CSDM-B）项目资助的项目中，加州大学戴维斯分校化学系的Tantillo教授正在使用现代计算化学方法来探索有机分子反应的反应性原理的极限。本研究的目的是提供对控制反应性的因素的基本理解，这些因素对预测实验室反应结果有用。这项研究将通过建立新的机制模型来推进机械有机化学的知识，包括那些基于非统计动态效应的模型，这些模型允许反应绕过轨道对称约束，获得激发态的异常反应性，并利用熵来控制选择性。除了通过这项研究发现的机制模型的基本重要性之外，该项目还将有助于培养学生（研究生和本科生，其中一些来自代表性不足的群体）在机械化学的多学科方法方面的能力，并使他们接触到使用这些技术的不同职业。此外，将开发并广泛分发用于教授学生反应过程中分子振动的教育资源，以及使盲人和视障学生能够使用应用计算化学的方法。本研究将集中于三类反应，每一类都有其独特的挑战：明显禁止的周环反应，显示与基态后过渡态分岔反应相似行为的光化学有机反应，以及具有熵控制选择性的有机反应。将分析和预测每种反应的非统计动态效应，并构建反应性和选择性的一般模型，并用于设计新的反应。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。

In this project, funded by the Chemical Structure, Dynamics & Mechanisms B (CSDM-B) Program of the Chemistry Division, Professor Tantillo of the Department of Chemistry at the University of California, Davis is using modern computational chemistry methods to explore the limits of reactivity principles for reactions of organic molecules. The goal of this research is to provide fundamental understanding of factors that control reactivity at a level useful for predicting laboratory reaction outcomes. This research will advance knowledge in mechanistic organic chemistry through the construction of new mechanistic models, including those based on non-statistical dynamic effects that allow reactions to circumvent orbital symmetry constraints, access unusual reactivity of excited states and utilize entropy to control selectivity. In addition to the fundamental importance of the mechanistic models uncovered through this research, the project will serve to train students (graduate and undergraduate, several from underrepresented groups) in multidisciplinary approaches to mechanistic chemistry and expose them to diverse careers that employ such techniques. In addition, educational resources for teaching students about molecular vibrations during reactions, and methods for making applied computational chemistry accessible to blind and visually impaired students, will be developed and widely distributed. This research will focus on three classes of reactions, each with its own unique challenges: apparently forbidden pericyclic reactions, photochemical organic reactions displaying behavior akin to that of reactions with ground state post-transition state bifurcations, and organic reactions with entropy-controlled selectivity. Non-statistical dynamic effects will be analyzed and predicted for each, and general models of reactivity and selectivity will be constructed and used to design new reactions.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.