Thermally switchable redox properties have been reported to be due to a change in the spin state of newly designed overcrowded ethylenes, which can adopt closed-shell folded and open-shell twisted forms. In this study, tetrathienylanthraquinodimethane derivatives were designed to be in thermal equilibrium between a more stable folded form and less stable but more donating twisted diradical in solution, so that the oxidation potential can be controlled by heating/cooling. This is the first example of a switching of redox properties based on a thermally equilibrated twisted diradical, which can be more readily oxidized to the twisted dication.

中文翻译：

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封闭壳折叠物种和开壳扭曲物种之间热平衡触发的氧化还原特性转换。

据报道，可热切换的氧化还原性能是由于新设计的过分拥挤的乙烯的自旋态发生了变化，这些乙烯可以采用闭壳折叠和开壳扭曲形式。在这项研究中，四噻吩基蒽醌二甲烷衍生物被设计为在溶液中更稳定的折叠形式与不稳定但给体更多的扭曲双自由基之间处于热平衡状态，从而可以通过加热/冷却来控制氧化电位。这是基于热平衡的扭曲双基自由基转换氧化还原性质的第一个示例，该自由基可以更容易地氧化成扭曲双阳离子。