Even in its oxidized state, a redox‐active guanidine is a Brønsted base that accepts two protons, realizing the first purely organic PCET reagent that can be diprotonated in its oxidized state. With trifluoroacetate counterions, low‐barrier hydrogen bonding is observed. Protonation has a dramatic effect on the redox chemistry.

中文翻译：

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双重氧化和双重质子化的氧化还原活性胍：质子耦合电子转移反应的终极中间体

即使处于氧化态，氧化还原活性胍也是一个布朗斯台德碱，它接受两个质子，从而实现了第一个纯有机PCET试剂，该试剂可以在氧化态下被双质子化。使用三氟乙酸抗衡离子时，观察到低势垒氢键。质子化对氧化还原化学有显着影响。