Weight Braden M, Weix Daniel J, Tonzetich Zachary J, Krauss Todd D, Huo Pengfei
Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, United States.
Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
J Am Chem Soc. 2024 Jun 12;146(23):16184-16193. doi: 10.1021/jacs.4c04045. Epub 2024 May 30.
Coupling molecules to a quantized radiation field inside an optical cavity has shown great promise to modify chemical reactivity. In this work, we show that the ground-state selectivity of the electrophilic bromination of nitrobenzene can be fundamentally changed by strongly coupling the reaction to the cavity, generating - or -substituted products instead of the product. Importantly, these are products that are not obtained from the same reaction outside the cavity. A recently developed approach was used to theoretically compute the relative energies of the cationic Wheland intermediates, which indicate the kinetically preferred bromination site for all products. Performing an analysis of the ground-state electron density for the Wheland intermediates inside and outside the cavity, we demonstrate how strong coupling induces reorganization of the molecular charge distribution, which in turn leads to different bromination sites directly dependent on the cavity conditions. Overall, the results presented here can be used to understand cavity induced changes to ground-state chemical reactivity from a mechanistic perspective as well as to directly connect frontier theoretical simulations to state-of-the-art, but realistic, experimental cavity conditions.
将分子与光学腔内的量子化辐射场耦合已显示出改变化学反应性的巨大潜力。在这项工作中，我们表明，通过将硝基苯的亲电溴化反应与腔强烈耦合，可从根本上改变其基态选择性，生成间位或对位取代产物而非邻位产物。重要的是，这些产物在腔外的相同反应中无法得到。采用最近开发的一种方法从理论上计算了阳离子惠兰中间体的相对能量，这些能量表明了所有产物动力学上优先的溴化位点。通过对腔内和腔外惠兰中间体的基态电子密度进行分析，我们证明了强耦合如何诱导分子电荷分布的重新排列，进而直接导致依赖于腔条件的不同溴化位点。总体而言，本文给出的结果可用于从机理角度理解腔诱导的基态化学反应性变化，以及将前沿理论模拟与先进但实际的实验腔条件直接联系起来。
