Modulation of the reactivity of metallofullerenes is critical for production of metallofullerene derivatives with desired properties and functionalities. In this study, we investigate the effects of reduction and oxidation on the reactivity and regioselectivity in Diels–Alder reaction of metallofullerene La@C₈₂ by means of density functional theory calculations. Because of the enhanced electron‐deficiency characteristic upon oxidation, the oxidized metallofullerene exhibits higher thermodynamic and kinetic reactivity as compared with neutral La@C₈₂. The regioselectivity in the reaction of La@C₈₂ with cylcopentadiene is remarkably changed after oxidation of the metallofullerene, which is explained in terms of the changes in the geometrical structure and the electronic structure of the metallofullerene. Quantitative analysis based on the activation‐strain model demonstrates that the low activation energy barrier for the reaction of the cation La@C₈₂⁺ with cyclopentadiene originates from small strain energy and large interaction energy between the reactants. Energy decomposition analysis on the transition states of the reactions reveals that the exchange‐repulsion interaction energy is one of the critical factors that determine the kinetic reactivity of the metallofullerene. This study not only provides new theoretical insights on how to modulate the reactivity of metallofullerenes, but also offers guideline for future experimental synthesis of new metallofullerene derivatives.

中文翻译：

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金属富勒烯La @ C82与环戊二烯Diels-Alder反应中反应性和区域选择性的氧化还原调节

金属富勒烯的反应性的调节对于生产具有所需性质和功能的金属富勒烯衍生物至关重要。在这项研究中，我们通过密度泛函理论计算研究了还原和氧化对金属富勒烯La @ C ₈₂的Diels-Alder反应中反应性和区域选择性的影响。由于氧化后增强的电子缺乏特性，与中性La @ C ₈₂相比，氧化的金属富勒烯具有更高的热力学和动力学反应活性。La @ C ₈₂反应中的区域选择性金属富勒烯的氧化后，环戊二烯的环氧基显着改变，这可以通过金属富勒烯的几何结构和电子结构的变化来解释。基于活化-应变模型的定量分析表明，低活化能垒对阳离子La @ C ₈₂ ⁺的反应与环戊二烯反应的产物来自小的应变能和反应物之间的大相互作用能。对反应过渡态的能量分解分析表明，交换排斥相互作用能是决定金属富勒烯动力学反应性的关键因素之一。这项研究不仅为如何调节金属富勒烯的反应性提供了新的理论见解，还为将来的新金属富勒烯衍生物的实验合成提供了指导。