Stoichiometric reduction reactions of two metal–organic frameworks (MOFs) by the solution reagents (M = Cr, Co) are described. The two MOFs contain clusters with Ti₈O₈ rings: Ti₈O₈(OH)₄(bdc)₆; bdc = terephthalate (MIL-125) and Ti₈O₈(OH)₄(bdc-NH₂)₆; bdc-NH₂ = 2-aminoterephthalate (NH₂-MIL-125). The stoichiometry of the redox reactions was probed using solution NMR methods. The extent of reduction is greatly enhanced by the presence of Na⁺, which is incorporated into the bulk of the material. The roughly 1 : 1 stoichiometry of electrons and cations indicates that the storage of e⁻ in the MOF is tightly coupled to a cation within the architecture, for charge balance.

中文翻译：

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含有钛簇的金属有机骨架的钠耦合电子转移反应性：阳离子在氧化还原化学中的重要性†

描述了溶液试剂（M = Cr、Co）对两种金属有机框架（MOF）的化学计量还原反应。这两个MOF包含带有Ti ₈ O ₈环的簇：Ti ₈ O ₈ (OH) ₄ (bdc) ₆；bdc=对苯二甲酸酯(MIL-125)和Ti ₈ O ₈ (OH) ₄ (bdc-NH ₂ ) ₆；bdc-NH ₂ = 2-氨基对苯二甲酸酯(NH ₂ -MIL-125)。使用溶液核磁共振方法探测氧化还原反应的化学计量。^{Na +}的存在大大增强了还原程度，Na + 融入到大部分材料中。电子和阳离子的大约 1:1 化学计量表明MOF 中存储的 e ^{-与结构内的阳离子紧密耦合，以实现电荷平衡。}