C22H14N2N1O9, triclinic, PI (no. 2), a = 9.589(5) A, b= 10.144(7) A, c = 11.312(5) A, a = 87.11(2)°, β = 72.38(2)°, γ = 64.96(2)°, V= 946.3 Ä 3 , Z= 2, Rgt(F) = 0.035, wRietfF 2 ) = 0.085, T= 173 K.
Source of materialSky blue block crystals of the title compound were synthesized by a hydrothermal method. All chemicals were of analytical purity grade and were used without further purification. A mixture of NiCh · 6H2O (1 mmol, 0.238 g), 1,2,4,5-benzenetetracarboxylic anhydride (1 mmol, 0.218 g), 1,10-phenanthroline monohydrate (1 mmol, 0.198 g), NaOH (2 mmol, 0.080 g) and distilled water (5 ml) was located into a 30 ml Teflon-lined reactor and heated at 160 °C for 4 days. After cooling to room temperature at ca. 5 K/h, blue block crystals were isolated and washed with water and ethanol for three times, then dried in ambient. Elemental analysis: found -C, 52.02 %; H, 2.84 %; N, 5.54 %; calc. for C 2 2Hi4N2Ni09 -C, 51.91 %; H, 2.77 %; N, 5.50 %.
DiscussionThe self-assembly of metal ions with aromatic carboxylates is a rapidly developing research field of modern coordination chemistry, because of the aggregation of metal ions and these carboxylate ligands in versatile binding modes, such as monodentate, chelating bidentate, bridging bidentate and bridging tridentate. Hereby, 1,2,4,5-benzenetetracarboxylic acid (H4TCB) is a good bridging ligand, and numerous complexes with H4TCB anions have been prepared, such as that of Co(II) [1][2][3], Νϊ(Π) [4,5], ΊΊ(Ι) [6], Cu(ü) [4,7,8], Ζη(Π) [9]. Especially, the metal-1,10-phenanthroline (phen) system has been well studied and displays a diversity of structures. The title compound, [Ni 2 (H2TCB)2(phen)2(H20)2]n, forms a 2D polymer. The Ni atom is six-coordinated by four Ο atoms from three pyromellitate anions (H2TCB) and one water molecule, and two Ν atoms from a phen ligand.