CAREER: Physical organic approach to obtaining chemomechanical reaction parameters of diverse functional groups

伊利诺伊大学厄巴纳-香槟分校化学系的Roman Boulatov教授得到了美国国家科学基金会有机和高分子化学项目的支持，进行有机合成，动力学测量和计算相结合的研究，以开发一种方法来获得不同官能团反应的化学力学参数。这些参数量化了反应速率如何受到作用在反应物的单个原子上的外部介观力的影响。他们需要对5纳米到50纳米之间尺度的过程动态进行建模。在这些尺度上，动力学通常由少数化学键的重排控制，其速率取决于数百万原子之间的非平衡相互作用。在这种情况下，无论是标准的化学动力学模型，也不是牛顿定律单独是不够的。在化学机械方法中，整个过程的动力学被建模为受外部机械力扰动的小分子反应。这种方法提供了一个机会，以了解强烈的当代感兴趣的现象，如ATP合酶的操作，生物运动，机械应力下的材料降解，和摩擦化学。刺激响应材料和推定的分子机械装置和自主纳米机械装置的合理设计需要潜在的化学反应的定量化学机械参数。PI的小组将开发小的（1 kDa）双功能分子，其中一个部分的光异构化（致动器）将在立体电子多样性官能团上施加超过1 nN的机械力（mechanophores）和非经验的方法，将机械力整合到化学动力学形式主义。这个职业奖的更广泛的影响在于开发一个简单的，量化外部介观力如何影响不同化学反应速率的一般方法。在开发和完善这种方法的过程中，PI的小组将获得原子的理解的约束力的影响的量子产率的光异构化和策略，以最大限度地提高产量的分子光致动器的合成修改和速率/力的关系，电环化反应和异裂和均裂的S-S键在各种实验条件下的断裂。拟议的研究将促进科学，技术，工程和数学（STEM）学科的人力资源开发，让服务不足的高中（HS）学生，HS STEM教师和第一代本科生在研究生和博士后研究员的指导下参与。两个方案将用于实现这一目标：- STIR（通过综合研究进行科学教学）：一个正在进行的PI领导的合作，旨在提高农村高中学生的科学素养。STIR整合了NSF计划的元素，如教师研究经验（RET），高中生研究经验（REHS）和K-12教育研究生教学研究员（GK-12）活动，并将同侪指导策略纳入HS化学教学。FIRST（培养研究、学习和教学的独立性）：这是一项综合性举措，旨在解决一所主要研究型大学的第一代大学生面临的具体需求和挑战。该项目的跨学科性质为国家下一代科学家提供了良好的培训基础。

Professor Roman Boulatov, of the Department of Chemistry at University of Illinois- Urbana-Champaign, is supported by the Organic and Macromolecular Chemistry Program at the National Science Foundation to perform research integrating organic synthesis, kinetic measurements and computations to develop a method to obtain chemomechanical parameters of reactions of diverse functional groups. Such parameters quantify how reaction rates are affected by external mesoscopic forces acting at individual atoms of the reactants. They are required to model the dynamics of processes at scales between 5 nm and 50 nm. At these scales the dynamics is often governed by rearrangements of a few chemical bonds at rates that depend on non-equilibrium interaction among millions of atoms. In this regime, neither the standard chemical kinetics models, nor Newton laws alone are adequate. Within the chemomechanical approach, the dynamics of the whole process is modeled as a small-molecule reaction perturbed by external mechanical forces. This approach provides an opportunity to understand phenomena of intense contemporary interest, such as operation of ATP-synthase, biological motility, degradation of materials under mechanical stress, and tribochemistry. The rational design of stimuli responsive materials and putative molecular mechanical devices and autonomous nanomechanical devices requires quantitative chemomechanical parameters of underlying chemical reactions. The PI's group will develop small (1 kDa) bifunctional molecules in which photoisomerization of one moiety (actuator) will exert mechanical forces over 1 nN on stereoelectronically diverse functional groups (mechanophores) and non-empirical approaches to integrate mechanical forces into chemical kinetics formalisms.Broader impacts of this CAREER award lie in the development of a simple, general method to quantify how external mesoscopic force affects rates of diverse chemical reactions. In the course of developing and refining this method the PI's group will obtain atomistic understanding of the effect of a restraining force on quantum yields of photoisomerization and strategies to maximize the yield by synthetic modifications of molecular photoactuators and rate/force relationships for electrocyclic reactions and heterolytic and homolytic scission of the S-S bond under various experimental conditions. The proposed research will facilitate human resource development in Science, Technology, Engineering and Mathematics (STEM) disciplines by involving underserved high-school (HS) students, HS STEM teachers and first-generation undergraduates under the guidance of graduate students, and postdoctoral fellows. Two Programs will be use to accomplish this:- STIR (Science Teaching through Integrated Research): an ongoing PI-lead collaboration aimed improving the scientific literacy of rural high school students. STIR integrates elements of NSF Programs such as Research Experience for Teachers (RET), Research Experience for High Schoolers (REHS), and Graduate Teaching Fellows in K-12 Education (GK-12) activities and incorporates peer-mentoring strategies into HS Chemistry teaching.- FIRST (Fostering Independence in Research, Studies and Teaching): a comprehensive initiative aimed at addressing specific needs and challenges faced by first-generation college students at a major research university.The interdisciplinary nature of the project forms an excellent training ground for the future generation of nation's scientists.