Crystal structures of two nickel compounds comprising neutral NiII hydrazone complexes and dicarboxylic acids

• 出版年: Acta Crystallographica Section E: Crystallographic Communications
• 主要な著者: Takumi Nakanishi, Osamu Sato
• フォーマット: 論文
• 言語: 英語
• 出版事項: International Union of Crystallography 2017-02-01
• 主題: crystal structure; hydrazone complex; hydrogen bond; dicarboxylic acid; halogen–halogen interactions; co-crystal
• オンライン･アクセス: http://scripts.iucr.org/cgi-bin/paper?S2056989016020326

Two isostructural NiII compounds, bis{N-[1-(pyridin-2-yl-κN)ethylidene]pyridine-4-carbohydrazonato-κ2N′,O}nickel(II)–2,5-dichloroterephthalic acid (1/1), [Ni(C13H11N4O)2](C8H4Cl2O4), and bis{N-[1-(pyridin-2-yl-κN)ethylidene]pyridine-4-carbohydrazonato-κ2N′,O}nickel(II)–2,5-dibromoterephthalic acid (1/1), [Ni(C13H11N4O)2](C8H4Br2O4), were synthesized and their crystal structures determined. The pair of N,N′,O-tridentate N-[1-(pyridin-2-yl-κN)ethyl]pyridine-4-carbohydrazonate L ligands result in a cis-NiO2N4 octahedral coordination sphere for the metal ions. The asymmetric units consist of two half-molecules of the dicarboxylic acids, which are completed by crystallographic inversion symmetry. In the respective crystals, the 2,5-dichloroterephthalic acid (H2Cl2TPA, 1-Cl) molecules form zigzag hydrogen-bonded chains with the [Ni(L)2] molecules, with the hydrogen-bond distances in 1-Br slightly longer than those in 1-Cl. The packing is consolidated by aromatic π–π stacking between the dicarboxylic acid molecules and terminal pyridine rings in [Ni(L)2] and short halogen–halogen interactions are also observed. The qualitative prediction of the H-atom position from the C—N—C angles of the terminal pyridine rings in L and the C—O distances in the carboxyl groups show that 1-Cl and 1-Br are co-crystals rather than salts.