Tris[hexa­amminecobalt(III)] bis­[tri­oxalato­cobaltate(II)] chloride dodeca­hydrate

Ruijng Tian; Yan Yan; Cailing Zhang; Liyan Wang; Qinhe Pan

doi:10.1107/S1600536812026414

. 2012 Jun 16;68(Pt 7):m914–m915. doi: 10.1107/S1600536812026414

Tris[hexaamminecobalt(III)] bis[trioxalatocobaltate(II)] chloride dodecahydrate

Ruijng Tian ^a, Yan Yan ^b, Cailing Zhang ^a, Liyan Wang ^a, Qinhe Pan ^a,^*

PMCID: PMC3393183 PMID: 22807751

Abstract

The title compound, [Co^III(NH₃)₆]₃[Co^II(C₂O₄)₃]₂Cl·12H₂O, was synthesized under hydrothermal conditions. The asymmetric unit comprises two [Co(NH₃)₆]³⁺ cations, one located on a threefold axis and the other on a site of symmetry -3, a [Co(C₂O₄)₃]⁴⁺ anion, located on a threefold axis, one sixth of a chloride anion [disordered over two sites, one threefold (site occupancy = 0.5) and the other -3 (site occupancy (0.25)] and two water molecules. Both Co^III centers are six-coordinated by NH₃ molecules, forming [Co(NH₃)₆]³⁺ octahedra, with Co—N distances in the range 1.958 (2)–1.977 (3) Å. The title structure gives the first example of the [Co(C₂O₄)₃]⁴⁻ anion, with the distorted octahedral environment of Co^II center formed by six O atoms from three oxalate residues. The Co—O bond lengths are 2.0817 (18) to 2.0979 (18) Å. Multiple N—H⋯O, N—H⋯Cl and O—H⋯O hydrogen bonds link the cations, anions and water molecules into a three-dimensional network.

Related literature

For metal phosphates and germanates templated by metal complexes, see: Wang et al. (2003 ▶, 2006 ▶); Pan et al. (2005 ▶, 2008 ▶). For our continued research interest, see: Pan et al. (2010a ▶,b ▶, 2011 ▶). For a compound containing the [Co^III(NH₃)₆]³⁺ cation, see: Wu et al. (2012 ▶).

Experimental

Crystal data

[Co(NH₃)₆][Co(C₂O₄)₃]Cl·12H₂O
M _r = 1381.02
Trigonal,
a = 12.2138 (4) Å
c = 9.9090 (8) Å
V = 1280.15 (12) Å³
Z = 1
Mo Kα radiation
μ = 1.75 mm⁻¹
T = 296 K
0.30 × 0.15 × 0.15 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T _min = 0.737, T _max = 0.769
7736 measured reflections
1923 independent reflections
1514 reflections with I > 2σ(I)
R _int = 0.030

Refinement

R[F ² > 2σ(F ²)] = 0.036
wR(F ²) = 0.108
S = 1.16
1923 reflections
115 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.61 e Å⁻³
Δρ_min = −1.09 e Å⁻³

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT (Bruker, 2005 ▶); data reduction: SAINT program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812026414/yk2060sup1.cif

e-68-0m914-sup1.cif^{(21.5KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812026414/yk2060Isup2.hkl

e-68-0m914-Isup2.hkl^{(94.7KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯Cl1′	0.89	2.62	3.176 (15)	121
N1—H1A⋯O1ⁱ	0.89	2.27	3.055 (4)	147
N1—H1B⋯O2ⁱⁱ	0.89	2.40	2.950 (4)	120
N1—H1B⋯O2ⁱⁱⁱ	0.89	2.52	3.151 (4)	128
N2—H2⋯O4^iv	0.91	2.09	2.993 (3)	171
N2—H2A⋯O1W	0.91	2.18	3.047 (4)	160
N2—H2B⋯O2W	0.91	2.15	2.958 (3)	147
N3—H3⋯O3^v	0.91	2.09	2.988 (3)	172
N3—H3A⋯O2W	0.91	2.19	3.051 (3)	157
N3—H3B⋯O1W	0.91	2.36	3.120 (4)	141
O1W—H1W⋯O1	0.87	2.13	2.971 (4)	162
O1W—H1WA⋯O1^vi	0.87	2.32	2.973 (4)	132
O2W—H2W⋯O2^vii	0.87	1.97	2.830 (3)	171
O2W—H2WA⋯O4^viii	0.87	2.06	2.868 (3)	154

Open in a new tab

Symmetry codes: (i) Inline graphic ; (ii) ; (iii) ; (iv) ; (v) ; (vi) ; (vii) ; (viii) .

Acknowledgments

This work was supported by the Program for New Century Excellent Talents in Universities (NCET-11–0929), the National Natural Science Foundation of China (No. 21101047), the Natural Science Foundation of Hainan Province (No. 211010) and the Priming Scientific Research Foundation of Hainan University (No. kyqd1051).

supplementary crystallographic information

Comment

Recently, more attention has been paid to employ transition metal complexes as templates for supramolecular structures, because they are versatile and can be made with a wide variety of shapes and charges. Up to now, transition metal cTris[hexaamminecobalt(III)] bis[trioxalatocobaltate(II)] chloride dodecahydrateomplexes have been introduced into the synthesis of various open-framework materials, including metal phosphates (Wang et al., 2003,2006), germanates (Pan et al., 2005,2008). Our continued interest has been focused on the synthesis of microporous open-framework metal-organic structures by introducing transition metal complexes as templates (Pan et al., 2010a,b,2011). Unexpectedly, in the reaction of Co(OAc)₂.4H₂O, Co(NH₃)₆Cl₃, and K₂C₂O₄ the title compound, [Co^III(NH₃)₆]₃[Co^II(C₂O₄)₃]₂.Cl.12H₂O, was obtained.

The title compound is composed of [Co(NH₃)₆]³⁺ cations, the counterions [Co(C₂O₄)₃]^4- and Cl^- anions, and two water molecules, as shown in Figure 1. The crystal structure contains two Co^III centers, one is located on a threefold rotation axis, and the other is located at a 3 position. Each Co^III center is six-coordinated by NH₃ molecules to form octahedral [Co(NH₃)₆]³⁺ cations, similar to that observed in [Co(NH₃)₆]₂(NO₃)Cl₅ (Wu et al., 2012). The Co—N distances are in the range 1.958 (2)–1.977 (3) Å. The crystal structure also contains one Co^II center, which is located on a threefold rotation axis. It is coordinted by six O atoms from three different oxalate residues to form [Co(C₂O₄)₃]^4- anion having a slightly distorted octahedral geometry, with the distances Co—O ranging from 2.0804 (17) to 2.0968 (17) Å. The Cl^- anion is splitted into two positions, Cl1 and Cl1'. The [Co(III)(NH₃)₆]³⁺ cations, [Co(II)(C₂O₄)₃]^4- anions, Cl^- anions, and water molecules form an extensive hydrogen-bonding network, with the distance of N—H···N hydrogen bonds of 2.751 (4) Å, the distance of N—H···Cl hydrogen bonds of 3.169 (9) Å, the distance of N—H···O hydrogen bonds in the range of 2.959 (3)–3.147 (3) Å, and the distance of O—H···O hydrogen bonds in the range of 2.829 (3)–2.973 (4) Å (Table 1).

Experimental

In a typical synthesis, a mixture of Co(OAc)₂.4H₂O (0.250 g), Co(NH₃)₆Cl₃ (0.1 g), K₂C₂O₄ (0.276 g), and H₂O (5 ml), was placed into a 20 ml Teflon-lined reactor and heated to 100 °C for 3 days under autogenous pressure. Orange rod-like crystals were obtained.