Neutral complexes [M^II(C₅Me₅)(Q²⁻)(NO⁺)] with M=Ru or Os and the catecholates Q²⁻ with 3,5‐di‐tert‐butyl (dtbc) or 3,4,5,6‐tetrachloro substituents (tcc) were identified with the oxidation and charge states indicated. Reversible electron transfer was analyzed spectroelectrochemically (EPR, UV‐vis‐NIR, IR), supported by DFT calculations. Reversible reduction was observed for [Ru(C₅Me₅)(tcc)(NO)] to occur on the nitrosyl ligand to yield the NO radical complex [Ru^II(C₅Me₅)(tcc²⁻)(NO^.)]⁻, whereas the stepwise oxidation yielded o‐semiquinone cations, [M^II(C₅Me₅)(Q^.−)(NO⁺)]⁺, and dications. The metals remained in the stable low‐spin d⁶ states, Ru^II and Os^II, respectively. Redox potentials were found to depend strongly on the donor or acceptor substitution pattern at Qⁿ.

中文翻译：

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络合物[M（C5Me5）（Q）（NO）] n，M = Ru或Os，Q = o-喹诺酮类中多个氧化还原位点的分析

具有M = Ru或Os的中性络合物[M ^II（C ₅ Me ₅）（Q ²⁻）（NO ⁺）]和具有3,5-二叔丁基（dtbc）或3,4的儿茶酚Q ²⁻确定了5,5,6-四氯取代基（tcc），并标明了其氧化和电荷状态。在DFT计算的支持下，对可逆电子转移进行了光谱电化学分析（EPR，UV-vis-NIR，IR）。在亚硝酰基配体上观察到[Ru（C ₅ Me ₅）（tcc）（NO）]可逆还原，生成NO自由基络合物[Ru ^II（C ₅ Me ₅）（tcc ²⁻）（NO）^。）] ^-，而逐步氧化会生成邻半醌阳离子[M ^II（C ₅ Me ₅）（Q ^.-）（NO ⁺）] ⁺和指示剂。金属分别保持在稳定的低旋转d ⁶状态，即Ru ^II和Os ^II。发现氧化还原电势在很大程度上取决于Q ⁿ上的供体或受体取代模式。