Harimoto Takashi, Kikuchi Moto, Suzuki Takanori, Ishigaki Yusuke
Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Japan.
Institute for Molecular Science, Myodaiji, Okazaki, Japan.
Nat Commun. 2025 May 8;16(1):4088. doi: 10.1038/s41467-025-59317-w.
π-Electron systems with multiple redox-active units have attracted attention in various fields due to their potential applications. However, the design strategy remains elusive to selectively synthesize the diverse molecular structures of redox-convertible species. In this study, covalently linked quinodimethane derivatives with a sulfur bridge [(ArQD)S] were designed as redox-active motifs that can be converted into three different geometries via redox reaction. Here we show that the favored geometry of the corresponding redox states of (ArQD)S can be precisely controlled by adjusting the steric bulk of the substituents on the aryl group to change the proximity of the quinodimethane units. Notably, this redox-mediated strategy also leads to the isolation and structural determination of the missing link with an o-diphenoquinoid structure, a diphenoquinoid isomer whose isolation had remained elusive for almost a century. Thus, this study provides a method that allows the modulation/control of electronically and/or thermodynamically stable structures, as well as their electronic and spectroscopic properties.
具有多个氧化还原活性单元的π电子体系因其潜在应用在各个领域受到关注。然而，选择性合成氧化还原可转换物种的多种分子结构的设计策略仍然难以捉摸。在本研究中，具有硫桥的共价连接醌二甲烷衍生物[(ArQD)S]被设计为可通过氧化还原反应转化为三种不同几何结构的氧化还原活性基序。在此我们表明，通过调节芳基上取代基的空间位阻以改变醌二甲烷单元的间距，可以精确控制(ArQD)S相应氧化还原态的优势几何结构。值得注意的是，这种氧化还原介导的策略还导致分离并确定了具有邻二酚醌结构的缺失环节的结构，邻二酚醌异构体的分离近一个世纪以来一直难以实现。因此，本研究提供了一种能够调节/控制电子和/或热力学稳定结构及其电子和光谱性质的方法。
