Crystal structure of catena-poly[[diaqua(benzoate-κO1)cobalt(II)]-μ-4,4'- bis-(1,2,4-triazol-1-ylmethyl)biphenyl-κ2-N:N'], [Co(C18H16N6)(C7H5O2)2(H2O)2]n, C32H30CoN6O6

Abstract

Source of materialThetitle compound was prepared under the hydrothermalconditions. Am ixture of CoCl 2 ·6H 2 O( 0.1 mmol, 23.7 mg), benzoic acid (0.1 mmol, 12.2 mg) and 4,4'-bis-(1,2,4-triazol-1-ylmethyl)biphenyl (btmb, 0.1 mmol, 31.6 mg) in distilled water (10 mL) was placed in a25mLTeflon-lined stainless steelvessel, which was heated at 130°C for three days, and then cooled to room temperature. Red block-shaped crystals were obtained. Experimental detailsHatoms were generatedgeometrically, and refined as riding atoms, with C-H=0.93Å(CH)and 0.97 Å(CH 2 ). Hatoms bound to Oatoms were foundfromdifferencemaps and refined with distancerestraintsofO-H =0.85 Å. All Hatoms were refined with U iso (H) =1.2 U eq (C, O). DiscussionConsiderable interest continues to be focused on the rational design and syntheses of novel coordination polymers, because of their intriguing architectures and their potential applications as functional materials [1,2].Auseful strategy to synthesize such networked compounds involves the selection of appropriate multidentate bridging ligands and metal ions displaying appropriate electronic and steric properties that will act in concert to promote the formation of desired polymeric architectures [3][4][5]. Thus, the flexible triazole-containing ligand 4,4'-bis-(1,2,4-triazol-1-ylmethyl)biphenyl(btmb) has widely been utilized to construct coordination polymers because of its variable conformations and versatile coordination modes [6][7][8][9]. Herein we present the title polymeric compound [Co(C 18 H 16 N 6 )(C 7 H 5 O 2 ) 2 (H 2 O) 2 ] n (I), assembled from btmb, benzoic acid and Co II.The asymmetric unit of (I)containsone Co II ion, onebenzoate ligand,halfabtmb ligand andone coordinated watermolecule. Each Co II ion lies on an inversion centre, and adopts adistorted octahedral geometry with two Natoms from two symmetry-related btmbligands and two Oa toms from two benzoate ligands in the equatorial positions and two water Oa toms in the axial positions. Each btmb ligand adopts atrans conformation bridging two Co II ions to generateazigzagpolymer chain. Furthermore, thechains of (I)are furtherl inkedt ogethert hrough interchain O-H···Oh ydrogen bonds between the coordinated water molecules and the carboxylate oxygen atomsw ith the O···O distance of 2.828 Å along the ab plane to produce an infinite two-dimentional layer.