Crystal structure of (oxalato-k2O:O')-[μ-1,1'-(1,6-hexanediyl)bis- (imidazole)-k2N:N']cobalt(II) hemihydrate, Co(C2O4)(C12H18N4) · 0.5H2O

Abstract

C14H19CoN4O4.50, monoclinic, C12/c1 (no. 15), a = 12.653(6) A, b = 13.888(6) A, c = 9.403(6) A, * = 100.49(3)°, V = 1624.7 A, Z = 4, Rgt(F) = 0.036, wRref(F ) = 0.086, T = 293 K. Source of material Amixture of CoCl2.·.6H2O (0.238 g, 1 mmol) and NaOH (0.08 g, 2.mmol) in water was stirred for 10 min at room temperature, and then 1,1'-(1,6-hexanediyl)bis(imidazole) (L, 0.432 g, 2 mmol) was added to the mixture. After stirring 0.5 h, the precipitate was dissolved by dropwise addition of an aqueous solution of NH3 (14.M, 5ml). Pink crystals were obtained after allowing the solution to stand at room temperature for several days. Experimental details AllH atoms onCatomswere generated geometrically and refined as riding atoms with d(C—H) = 0.93A andUiso(H) = 1.2Ueq(C). The water H atoms were not included in the model. Discussion In recent years, the bis(imidazole) ligands, as an important family of flexible N-donor ligands, have attracted a great interest [1]. A series of fascinating carboxylate polymers based on 1,1'-(1,4butanediyl)bis(imidazole) ligand have been reported [2]. By contrast, the exploratrion of carboxylate polymers constructed from 1,1'-(1,6-hexanediyl)bis(imidazole) (L) is relatively less developed [3]. In the title crystal structure, each cobalt cation is six-coordinated by four O atoms from two oxalate anions and two N atoms from two L ligands forming a slightly distorted octahedron. The bond lengths of Co—O and Co—N are similar to the reported values [4]. The cobalt cations are connected by oxalate anions to form chains, which are further bridged by L ligands to give a twodimensional layer. Z. Kristallogr. NCS 224 (2009) 663-664 / DOI 10.1524/ncrs.2009.0292 663 © by Oldenbourg Wissenschaftsverlag, Munchen Crystal: pink block, size 0.12 × 0.16 × 0.23 mm Wavelength: Mo K+ radiation (0.71069 A) .: 10.85 cm−1 Diffractometer, scan mode: Bruker APEX CCD, % 2,max: 54.96° N(hkl)measured, N(hkl)unique: 7856, 1862 Criterion for Iobs, N(hkl)gt: Iobs > 2 )(Iobs), 1620 N(param)refined: 107 Programs: SHELXS-97 [5], SHELXL-97 [6] Table 1. Data collection and handling. H(1) 8f 0.4531 0.2500 1.0001 0.049 H(2) 8f 0.2798 0.2789 0.6149 0.062 H(3) 8f 0.2025 0.1465 0.7336 0.068 H(4A) 8f 0.2394 0.0988 1.0315 0.071 H(4B) 8f 0.3594 0.1160 1.1056 0.071 H(5A) 8f 0.2916 −0.0164 0.8806 0.074 H(5B) 8f 0.3338 −0.0449 1.0420 0.074 H(6A) 8f 0.4636 −0.0710 0.8964 0.068 H(6B) 8f 0.4639 0.0392 0.8621 0.068 O(1W) 4e 0.50 1⁄2 0.2815(8) 1⁄2 0.153(4) Table 2. Atomic coordinates and displacement parameters (in A). Atom Site Occ. x y z Uiso