Abstract Di-2-pyridyl ketone p-nitrophenoxyacetic acid hydrazone (1), obtained from acid-catalyzed condensation of di-2-pyridyl ketone (dpk) with p-nitrophenoxyacetic acid hydrazide, reacts with Re(CO)5Cl in refluxing toluene to form fac-Re(CO)3(κ2-Npy,Npy-dpknxh)Cl (2). 1 and 2 were identified from the results of their elemental analyses, spectroscopic and electrochemical properties. X-ray structural analysis on single crystals of 1 and 2 grown from CH3CN solutions and fac-Re(CO)3(κ2-Npy,Npy-dpknxh)Cl·DMSO (3) grown from a DMSO solution of 2 confirmed their identities. Spectrophotometric titrations of protophilic solutions of 2 with protophilic solutions of NaBX4 (X = H or F) divulged inter-conversion between the high- and low-energy ILCT transitions of 2 and its solvated complex. Substrates in low concentrations can be detected and determined using protophilic solutions of 2. Electrochemical measurements on 1 and 2 disclosed irreversible redox transformations leading to decomposition of 1 and 2 following the first electron transfer. Graphical Abstract

中文翻译：

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二-2-吡啶基酮对硝基苯氧乙酸腙(dpknxh)、fac-Re(CO)3(κ2-Npy,Npy-dpknxh)Cl的第一种金属化合物的理化性质

摘要 二-2-吡啶基酮对硝基苯氧乙酸腙 (1) 由二-2-吡啶基酮 (dpk) 与对硝基苯氧乙酸酰肼进行酸催化缩合得到，在回流甲苯中与 Re(CO)5Cl 反应生成形成 fac-Re(CO)3(κ2-Npy,Npy-dpknxh)Cl (2)。1 和 2 是根据元素分析、光谱和电化学性质的结果确定的。从 CH3CN 溶液中生长的 1 和 2 的单晶和从 2 的 DMSO 溶液中生长的 fac-Re(CO)3(κ2-Npy,Npy-dpknxh)Cl·DMSO (3) 的 X 射线结构分析证实了它们的身份。用 NaBX4（X = H 或 F）的亲原溶液对 2 的亲原溶液进行分光光度滴定，揭示了 2 及其溶剂化复合物的高能和低能 ILCT 跃迁之间的相互转化。可以使用 2 的亲原性溶液检测和测定低浓度的底物。对 1 和 2 的电化学测量公开了不可逆氧化还原转化，导致在第一次电子转移后分解 1 和 2。图形概要