Nakanishi Takumi, Sato Osamu
Institute for Materials Chemistry and Engineering, Kyushu University, 744 Motoka, Nishi-ku, Fukuoka 819-0395, Japan.
Acta Crystallogr E Crystallogr Commun. 2017 Jan 6;73(Pt 2):103-106. doi: 10.1107/S2056989016020326. eCollection 2017 Feb 1.
Two isostructural Ni compounds, bis-{-[1-(pyridin-2-yl-κ)eth-ylidene]pyridine-4-carbohydrazonato-κ',}nickel(II)-2,5-di-chloro-terephthalic acid (1/1), Ni(CHNO), and bis-{-[1-(pyridin-2-yl-κ)eth-ylidene]pyridine-4-carbohydrazonato-κ',}nickel(II)-2,5-di-bromo-terephthalic acid (1/1), Ni(CHNO), were synthesized and their crystal structures determined. The pair of ,',-tridentate -[1-(pyridin-2-yl-κ)eth-yl]pyridine-4-carbohydrazonate ligands result in a -NiON octa-hedral coordination sphere for the metal ions. The asymmetric units consist of two half-mol-ecules of the di-carb-oxy-lic acids, which are completed by crystallographic inversion symmetry. In the respective crystals, the 2,5-di-chloro-terephthalic acid (HClTPA, ) mol-ecules form zigzag hydrogen-bonded chains with the [Ni()] mol-ecules, with the hydrogen-bond distances in slightly longer than those in . The packing is consolidated by aromatic π-π stacking between the di-carb-oxy-lic acid mol-ecules and terminal pyridine rings in [Ni()] and short halogen-halogen inter-actions are also observed. The qualitative prediction of the H-atom position from the C-N-C angles of the terminal pyridine rings in and the C-O distances in the carboxyl groups show that and are co-crystals rather than salts.
合成了两种同构的镍化合物，双-{-[1-(吡啶-2-基-κ)乙叉基]吡啶-4-碳酰肼基-κ',}镍(II)-2,5-二氯对苯二甲酸(1/1)，Ni(C₁₀H₉N₃O)₂，以及双-{-[1-(吡啶-2-基-κ)乙叉基]吡啶-4-碳酰肼基-κ',}镍(II)-2,5-二溴对苯二甲酸(1/1)，Ni(C₁₀H₉N₃O)₂，并测定了它们的晶体结构。一对',-三齿的-[1-(吡啶-2-基-κ)乙]吡啶-4-碳酰肼酸配体为金属离子形成了一个-NiON八面体配位球。不对称单元由二羧酸的两个半分子组成，通过晶体学倒转对称性完成。在各自的晶体中，2,5-二氯对苯二甲酸(HClTPA, )分子与[Ni()]分子形成锯齿状氢键链，其中的氢键距离略长于中的氢键距离。堆积通过二羧酸分子与[Ni()]中的末端吡啶环之间的芳香π-π堆积得到巩固，并且还观察到短的卤素-卤素相互作用。根据末端吡啶环的C-N-C角和羧基中的C-O距离对H原子位置的定性预测表明，和是共晶体而非盐。
