CEA-DRF-BIG-LCBM-BioCE, Univ. Grenoble Alpes, CNRS UMR 5249 , 17 rue des Martyrs , 38054 Grenoble , France.
Institut des Sciences Moléculaires de Marseille, Aix Marseille Université, CNRS, Centrale Marseille, ISM2 UMR 7313 , 13097 Marseille , France.
Inorg Chem. 2019 Sep 3;58(17):11649-11655. doi: 10.1021/acs.inorgchem.9b01594. Epub 2019 Aug 22.
A new mixed-valent dicopper complex was generated from ligand exchange by dissolving a bis(CHCN) precursor in acetone. Introduction of a water molecule in place of an acetonitrile ligand was evidenced by base titration and the presence of a remaining coordinated CHCN by IR, F NMR, and theoretical methods. The proposed structure (CHCN-Cu-(SR)-Cu-OH) was successfully DFT-optimized and the calculated parameters are in agreement with the experimental data. has a unique temperature-dependence EPR behavior, with a localized valence from 10 to 120 K that undergoes delocalized at room temperature. The electrochemical signatures are in the line of the other parent and sensibly different from the rest of the series. Similar to the case of , was finally capable of single turnover NO reduction at room temperature. N was detected by GC-MS, and the redox character was confirmed by EPR and ESI-MS. Kinetic data indicate a reaction rate order close to 1 and a rate 10 times faster compared to . is thus the second example of that kind and highlights not only the main role of the Cu-OH motif, but also that the adjacent Cu-X partner (X = OTf in and CHCN in ) is a new actor in the casting to establish structure/activity correlations.
一种新的混合价双核铜配合物是通过在丙酮中溶解双（CHCN）前体进行配体交换生成的。通过碱滴定和 IR、F NMR 和理论方法证实了一个水分子取代一个乙腈配体的存在。提出的结构（CHCN-Cu-(SR)-Cu-OH）成功地进行了 DFT 优化，计算参数与实验数据一致。该配合物具有独特的温度依赖 EPR 行为，其局部价态在 10 至 120 K 之间，在室温下发生离域。电化学特征与其他母体一致，与该系列的其余部分明显不同。与 [Cu(OTf)2(phen)] 类似，[Cu(CH3CN)2(phen)(SR)] 最终能够在室温下进行单电子 NO 还原。通过 GC-MS 检测到 N，通过 EPR 和 ESI-MS 确认了氧化还原特征。动力学数据表明反应速率接近 1，且比[Cu(OTf)2(phen)]快 10 倍。因此，它是此类的第二个例子，不仅突出了 Cu-OH 基序的主要作用，而且相邻的 Cu-X 配体（在 [Cu(OTf)2(phen)] 中为 OTf，在 [Cu(CH3CN)2(phen)(SR)] 中为 CH3CN）也是建立结构/活性相关性的新因素。
