Oxidation Potential Gap (ΔEox): The Hidden Parameter in Redox Chemistry
Oxidation Potential Gap (ΔEox): The Hidden Parameter in Redox Chemistry
复制标题
氧化电位差 (ΔEox)：氧化还原化学中的隐藏参数
DOI：
10.1002/anie.202206064
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
K.
中科院分区：
文献类型：
--
作者：
Okamoto;K.; Shida;N.; Morizumi;H.; Kitano;Y.; Chiba;K.
具有不同电子特征的芳基的氧化联芳基偶联通常是失败的。然而，目前还没有通过理论分析对其进行系统的研究，因此，影响耦合效率的关键因素还不清楚。在这里，我们提出“氧化电势差(ΔE0x)”是预测分子内氧化偶联反应效率的关键参数，ΔE0x被定义为相关芳环的氧化电势之差。我们的实验和计算分析表明，芳香族分子内偶联反应的效率与自由基阳离子中间体的C、−、C键形成的活化能(Δ、E、≠)有关。此外，ΔE≠与ΔEOX相关。因此，我们展示了通过连接可切割的额外供电子/吸电子基团来调节ΔEox.，使得能够使用带有电子间隙的芳环来合理地合成菲替里酮骨架。
Oxidative biaryl coupling of aryls with different electronic features generally fails. However, this has not been systematically studied via theoretical analysis, and thus, the crucial factor governing coupling efficiency remains unclear. Herein, we propose that the “oxidation potential gap (ΔEox)” is a key parameter in predicting the efficiency of an intramolecular oxidative coupling reaction, with ΔEoxdefined as a difference in the oxidation potentials of the relevant aromatic rings. Our experimental and computational analyses revealed that the efficiency of an aromatic intramolecular coupling reaction correlates with the activation energy (ΔE≠) of C−C bond formation of the radical cation intermediates. Furthermore, ΔE≠correlates with ΔEox. Therefore, we demonstrate the tuning of ΔEoxby attaching cleavable extra electron‐donating/‐withdrawing groups, enabling the rational synthesis of a phenanthridone skeleton using aromatic rings with an electronic gap.