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metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 10| October 2012| Page m1246
https://doi.org/10.1107/S1600536812037579

Di­aqua­bis­­(1H-imidazole-4-carboxyl­ato-κ2N3,O)cobalt(II)

Wen-Sen Chena*

aSchool of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China
*Correspondence e-mail: chenws57@yahoo.com.cn

(Received 4 August 2012; accepted 31 August 2012; online 8 September 2012)

In the title compound, [Co(C4H3N2O2)2(H2O)2], the CoII ion is located on a twofold rotation axis and shows a distorted octa­hedral coordination configuration, defined by two N,O-bidentate 1H-imidazole-4-carboxyl­ate ligands in the equatorial plane and two water mol­ecules in the axial positions. In the crystal, O—H⋯O and N—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional supra­molecular network. π–π stacking inter­actions between the imidazole rings [centroid–centroid distances = 3.4914 (15) and 3.6167 (15) Å] further stabilize the crystal structure.

Related literature

For related structures, see: Cai et al. (2012[Cai, S.-L., Pan, M., Zheng, S.-R., Tan, J.-B., Fan, J. & Zhang, W.-G. (2012). CrystEngComm, 14, 2308-2315.]); Gryz et al. (2007[Gryz, M., Starosta, W. & Leciejewicz, J. (2007). J. Coord. Chem. 60, 539-546.]); Haggag (2005[Haggag, S. S. (2005). Egypt. J. Chem. 48, 27-41.]); Shuai et al. (2011[Shuai, W., Cai, S. & Zheng, S. (2011). Acta Cryst. E67, m897.]); Starosta & Leciejewicz (2006[Starosta, W. & Leciejewicz, J. (2006). Acta Cryst. E62, m2648-m2650.]); Yin et al. (2009[Yin, W.-P., Li, Y.-G., Mei, X.-L. & Yao, J.-C. (2009). Chin. J. Struct. Chem. 28, 1155-1159.]); Zheng et al. (2011[Zheng, S., Cai, S., Fan, J. & Zhang, W. (2011). Acta Cryst. E67, m865.]).

[Scheme 1]

Experimental

Crystal data

  • [Co(C4H3N2O2)2(H2O)2]

  • Mr = 317.13

  • Orthorhombic, P c c n

  • a = 7.1216 (18) Å

  • b = 11.780 (3) Å

  • c = 13.536 (3) Å

  • V = 1135.6 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 1.54 mm−1

  • T = 298 K

  • 0.35 × 0.33 × 0.30 mm
Data collection

  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2001[Bruker (2001). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.614, Tmax = 0.655

  • 6171 measured reflections

  • 1238 independent reflections

  • 1050 reflections with I > 2σ(I)

  • Rint = 0.024
Refinement

  • R[F2 > 2σ(F2)] = 0.027

  • wR(F2) = 0.073

  • S = 1.08

  • 1238 reflections

  • 87 parameters

  • H-atom parameters constrained

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.25 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1W—H1WA⋯O2i 0.87 1.99 2.827 (2) 162
O1W—H1WB⋯O2ii 0.86 1.93 2.771 (2) 166
N2—H2⋯O2iii 0.86 1.92 2.771 (2) 173
Symmetry codes: (i) [-x+2, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [-x+{\script{5\over 2}}, -y+{\script{1\over 2}}, z]; (iii) [-x+{\script{5\over 2}}, y, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEPIII (Burnett & Johnson, 1996[Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536812037579/hy2579sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812037579/hy2579Isup2.hkl

checkCIF report


Comment top

There is currently much interest in adopting heterocyclic carboxylic acids as multidentate ligands to prepare new metal coordination polymers. The main reason is that they have versatile coordination behaviors and can form high-dimensional polymers via hydrogen-bonding interactions in the process of self-assembly. 1H-Imidazole-4-carboxylic acid (H2imc), containing two N atoms of an imidazole group and one carboxylate group, is an excellent candidate for the construction of new coordination polymers. Up to this date, one-, two- and three-dimensional coordination polymers based on the H2imc ligand have been documented (Cai et al., 2012; Haggag, 2005; Gryz et al., 2007; Shuai et al., 2011; Starosta & Leciejewicz, 2006; Yin et al., 2009; Zheng et al., 2011). For example, the mononuclear complexes [Cd(Himc)2(H2O)2] and [Zn(Himc)2(H2O)2] have been reported by Yin et al. (2009) and Shuai et al. (2011), repectively. In this work, we report a Co(II) coordination polymer, [Co(Himc)2(H2O)2], which is isomorphous with the Cd(II) and Zn(II) analogs.

The asymmetric unit of the title compound contains a half of CoII ion, lying on a twofold rotation axis, one Himc anion and one coordinated water molecule. As illustrated in Fig. 1, the CoII ion is six-coordinated by two N and two O atoms from two cis-oriented N,O-bidentate Himc ligands in the equatorial plane, and two water molecules in the axial positions, forming a slightly distorted octahedral geometry. The Co—N bond length is 2.0786 (16) Å and the Co—O distances are 2.1088 (15) and 2.1793 (14) Å, which are comparable to those of the CdII and ZnII analogs. In the crystal structure, a pairs of intermolecular O—H···O hydrogen bonds (Table 1) involving the coordinated water (O1W) and the carboxylate O atom (O2) link the molecules into a two-dimensional network in the ab plane (Fig. 2). In addition, there exist strong π–π stacking interactions between the imidazole rings in the layer, with a centroid–centroid distatance of 3.4914 (15) Å. These layers are further connected by N—H···O hydrogen bonds (Table 1) involving the imidazole N atom (N2) and the carboxylate O atom (O2), generating a three-dimensional supramolecular network. Another type of π–π stacking interactions with a centroid–centroid distatance of 3.6167 (15) Å also can be observed between the neighbouring layers (Fig. 3).

Related literature top

For related structures, see: Cai et al. (2012); Gryz et al. (2007); Haggag (2005); Shuai et al. (2011); Starosta & Leciejewicz (2006); Yin et al. (2009); Zheng et al. (2011).

Experimental top

A mixture of CoCl2.6H2O (0.20 mmol), H2imc (0.20 mmol) and 6 ml EtOH/H2O (v/v 1:1) was sealed into a 10 ml sample bottle reactor and heated at 373 K for 48 h under autogenous pressure, and then slowly cooled to room temperature at a rate of 2 K/h. Red block crystals of the title compound were isolated, washed with distilled water, and dried in air (yield: 45%).

Refinement top

C- and N-bound H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93 and N—H = 0.86 Å and with Uiso(H) = 1.2Ueq(C, N). H atoms of the water molecule were located from a difference Fourier map and refined as riding, with O—H bond lenghts restrained to 0.86 Å.

Structure description top

There is currently much interest in adopting heterocyclic carboxylic acids as multidentate ligands to prepare new metal coordination polymers. The main reason is that they have versatile coordination behaviors and can form high-dimensional polymers via hydrogen-bonding interactions in the process of self-assembly. 1H-Imidazole-4-carboxylic acid (H2imc), containing two N atoms of an imidazole group and one carboxylate group, is an excellent candidate for the construction of new coordination polymers. Up to this date, one-, two- and three-dimensional coordination polymers based on the H2imc ligand have been documented (Cai et al., 2012; Haggag, 2005; Gryz et al., 2007; Shuai et al., 2011; Starosta & Leciejewicz, 2006; Yin et al., 2009; Zheng et al., 2011). For example, the mononuclear complexes [Cd(Himc)2(H2O)2] and [Zn(Himc)2(H2O)2] have been reported by Yin et al. (2009) and Shuai et al. (2011), repectively. In this work, we report a Co(II) coordination polymer, [Co(Himc)2(H2O)2], which is isomorphous with the Cd(II) and Zn(II) analogs.

The asymmetric unit of the title compound contains a half of CoII ion, lying on a twofold rotation axis, one Himc anion and one coordinated water molecule. As illustrated in Fig. 1, the CoII ion is six-coordinated by two N and two O atoms from two cis-oriented N,O-bidentate Himc ligands in the equatorial plane, and two water molecules in the axial positions, forming a slightly distorted octahedral geometry. The Co—N bond length is 2.0786 (16) Å and the Co—O distances are 2.1088 (15) and 2.1793 (14) Å, which are comparable to those of the CdII and ZnII analogs. In the crystal structure, a pairs of intermolecular O—H···O hydrogen bonds (Table 1) involving the coordinated water (O1W) and the carboxylate O atom (O2) link the molecules into a two-dimensional network in the ab plane (Fig. 2). In addition, there exist strong π–π stacking interactions between the imidazole rings in the layer, with a centroid–centroid distatance of 3.4914 (15) Å. These layers are further connected by N—H···O hydrogen bonds (Table 1) involving the imidazole N atom (N2) and the carboxylate O atom (O2), generating a three-dimensional supramolecular network. Another type of π–π stacking interactions with a centroid–centroid distatance of 3.6167 (15) Å also can be observed between the neighbouring layers (Fig. 3).

For related structures, see: Cai et al. (2012); Gryz et al. (2007); Haggag (2005); Shuai et al. (2011); Starosta & Leciejewicz (2006); Yin et al. (2009); Zheng et al. (2011).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level. [Symmetry code: (i) -x+3/2, -y+1/2, z.]
[Figure 2] Fig. 2. The crystal packing of the title compound, showing the two-dimensional network. Hydrogen bonds and π–π staking interactions are shown as dashed lines.
[Figure 3] Fig. 3. The crystal packing of the title compound, showing the three-dimensional supramolecular network. Hydrogen bonds and π–π staking interactions are shown as dashed lines.
Diaquabis(1H-imidazole-4-carboxylato- κ2N3,O)cobalt(II) top
Crystal data top
[Co(C4H3N2O2)2(H2O)2]F(000) = 644
Mr = 317.13Dx = 1.855 Mg m−3
Orthorhombic, PccnMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ab 2acCell parameters from 2075 reflections
a = 7.1216 (18) Åθ = 3.0–27.3°
b = 11.780 (3) ŵ = 1.54 mm−1
c = 13.536 (3) ÅT = 298 K
V = 1135.6 (5) Å3Block, red
Z = 40.35 × 0.33 × 0.30 mm
Data collection top
Bruker APEXII CCD
diffractometer		1238 independent reflections
Radiation source: fine-focus sealed tube1050 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
φ and ω scansθmax = 27.0°, θmin = 3.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)		h = −9→9
Tmin = 0.614, Tmax = 0.655k = −12→15
6171 measured reflectionsl = −17→16
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.027Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.073H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0317P)2 + 0.7299P]
where P = (Fo2 + 2Fc2)/3
1238 reflections(Δ/σ)max < 0.001
87 parametersΔρmax = 0.29 e Å−3
0 restraintsΔρmin = −0.25 e Å−3
Crystal data top
[Co(C4H3N2O2)2(H2O)2]V = 1135.6 (5) Å3
Mr = 317.13Z = 4
Orthorhombic, PccnMo Kα radiation
a = 7.1216 (18) ŵ = 1.54 mm−1
b = 11.780 (3) ÅT = 298 K
c = 13.536 (3) Å0.35 × 0.33 × 0.30 mm
Data collection top
Bruker APEXII CCD
diffractometer		1238 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)		1050 reflections with I > 2σ(I)
Tmin = 0.614, Tmax = 0.655Rint = 0.024
6171 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0270 restraints
wR(F2) = 0.073H-atom parameters constrained
S = 1.08Δρmax = 0.29 e Å−3
1238 reflectionsΔρmin = −0.25 e Å−3
87 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2sigma(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Co10.75000.25000.13193 (2)0.02397 (14)
O10.95746 (19)0.17187 (13)0.22880 (10)0.0305 (3)
O1W0.8973 (2)0.40251 (13)0.15738 (11)0.0351 (4)
O21.23719 (18)0.08486 (12)0.22678 (10)0.0302 (3)
N10.9449 (2)0.18857 (14)0.03090 (11)0.0270 (4)
C31.2150 (3)0.09661 (18)0.00537 (15)0.0304 (4)
H31.32620.05690.01550.036*
C11.0961 (3)0.12982 (16)0.18488 (14)0.0243 (4)
C21.0934 (3)0.13421 (16)0.07551 (14)0.0235 (4)
C40.9791 (3)0.18410 (18)−0.06466 (14)0.0314 (5)
H40.90180.2150−0.11310.038*
N21.1403 (2)0.12911 (15)−0.08276 (12)0.0327 (4)
H21.18820.1166−0.14010.039*
H1WA0.83640.44810.19620.039*
H1WB1.00720.39500.18330.039*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0206 (2)0.0304 (2)0.0209 (2)0.00483 (15)0.0000.000
O10.0258 (8)0.0427 (8)0.0230 (7)0.0060 (6)0.0011 (6)−0.0005 (6)
O1W0.0241 (8)0.0367 (8)0.0445 (9)0.0039 (6)−0.0032 (6)−0.0095 (7)
O20.0225 (7)0.0413 (8)0.0267 (7)0.0027 (6)−0.0034 (6)0.0047 (6)
N10.0252 (9)0.0331 (9)0.0226 (8)0.0046 (7)0.0017 (6)0.0016 (7)
C30.0258 (10)0.0356 (11)0.0297 (10)0.0038 (8)0.0005 (8)−0.0026 (9)
C10.0233 (10)0.0246 (9)0.0251 (9)−0.0032 (7)−0.0019 (8)0.0010 (8)
C20.0218 (10)0.0251 (9)0.0237 (9)0.0005 (7)−0.0002 (7)0.0007 (7)
C40.0303 (11)0.0408 (12)0.0230 (10)0.0041 (9)0.0004 (8)0.0031 (9)
N20.0327 (10)0.0424 (10)0.0231 (8)0.0023 (8)0.0073 (7)−0.0015 (7)
Geometric parameters (Å, º) top
Co1—N12.0786 (16)N1—C21.376 (2)
Co1—O1W2.1088 (15)C3—C21.359 (3)
Co1—O12.1793 (14)C3—N21.361 (3)
O1—C11.254 (2)C3—H30.9300
O1W—H1WA0.87C1—C21.482 (3)
O1W—H1WB0.86C4—N21.341 (3)
O2—C11.269 (2)C4—H40.9300
N1—C41.317 (2)N2—H20.8600
N1i—Co1—N197.72 (9)C4—N1—C2105.69 (16)
N1i—Co1—O1W98.23 (6)C4—N1—Co1141.57 (14)
N1—Co1—O1W94.12 (6)C2—N1—Co1112.73 (12)
N1i—Co1—O1Wi94.12 (6)C2—C3—N2105.76 (18)
N1—Co1—O1Wi98.23 (6)C2—C3—H3127.1
O1W—Co1—O1Wi161.19 (9)N2—C3—H3127.1
N1i—Co1—O1174.63 (6)O1—C1—O2125.17 (18)
N1—Co1—O178.23 (6)O1—C1—C2116.70 (16)
O1W—Co1—O185.65 (6)O2—C1—C2118.13 (17)
O1Wi—Co1—O183.06 (6)C3—C2—N1109.55 (17)
N1i—Co1—O1i78.23 (6)C3—C2—C1132.70 (18)
N1—Co1—O1i174.63 (6)N1—C2—C1117.72 (16)
O1W—Co1—O1i83.06 (6)N1—C4—N2110.91 (18)
O1Wi—Co1—O1i85.65 (6)N1—C4—H4124.5
O1—Co1—O1i106.02 (7)N2—C4—H4124.5
C1—O1—Co1114.54 (12)C4—N2—C3108.07 (17)
Co1—O1W—H1WA112.2C4—N2—H2126.0
Co1—O1W—H1WB115.5C3—N2—H2126.0
H1WA—O1W—H1WB105.7
N1—Co1—O1—C11.74 (14)N2—C3—C2—N10.4 (2)
O1W—Co1—O1—C1−93.39 (14)N2—C3—C2—C1−177.63 (19)
O1Wi—Co1—O1—C1101.68 (14)C4—N1—C2—C3−0.5 (2)
O1i—Co1—O1—C1−174.89 (15)Co1—N1—C2—C3−179.88 (13)
N1i—Co1—N1—C44.6 (2)C4—N1—C2—C1177.83 (17)
O1W—Co1—N1—C4−94.3 (2)Co1—N1—C2—C1−1.5 (2)
O1Wi—Co1—N1—C499.9 (2)O1—C1—C2—C3−179.0 (2)
O1—Co1—N1—C4−179.0 (2)O2—C1—C2—C31.4 (3)
N1i—Co1—N1—C2−176.42 (16)O1—C1—C2—N13.1 (2)
O1W—Co1—N1—C284.68 (14)O2—C1—C2—N1−176.53 (17)
O1Wi—Co1—N1—C2−81.10 (14)C2—N1—C4—N20.5 (2)
O1—Co1—N1—C20.00 (13)Co1—N1—C4—N2179.49 (16)
Co1—O1—C1—O2176.63 (15)N1—C4—N2—C3−0.2 (2)
Co1—O1—C1—C2−3.0 (2)C2—C3—N2—C4−0.1 (2)
Symmetry code: (i) −x+3/2, −y+1/2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···O2ii0.871.992.827 (2)162
O1W—H1WB···O2iii0.861.932.771 (2)166
N2—H2···O2iv0.861.922.771 (2)173
Symmetry codes: (ii) −x+2, y+1/2, −z+1/2; (iii) −x+5/2, −y+1/2, z; (iv) −x+5/2, y, z−1/2.

Experimental details

Crystal data
Chemical formula[Co(C4H3N2O2)2(H2O)2]
Mr317.13
Crystal system, space groupOrthorhombic, Pccn
Temperature (K)298
a, b, c (Å)7.1216 (18), 11.780 (3), 13.536 (3)
V (Å3)1135.6 (5)
Z4
Radiation typeMo Kα
µ (mm−1)1.54
Crystal size (mm)0.35 × 0.33 × 0.30
Data collection
DiffractometerBruker APEXII CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2001)
Tmin, Tmax0.614, 0.655
No. of measured, independent and
observed [I > 2σ(I)] reflections		6171, 1238, 1050
Rint0.024
(sin θ/λ)max (Å−1)0.639
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.027, 0.073, 1.08
No. of reflections1238
No. of parameters87
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.29, −0.25

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···O2i0.871.992.827 (2)162
O1W—H1WB···O2ii0.861.932.771 (2)166
N2—H2···O2iii0.861.922.771 (2)173
Symmetry codes: (i) −x+2, y+1/2, −z+1/2; (ii) −x+5/2, −y+1/2, z; (iii) −x+5/2, y, z−1/2.
 

Acknowledgements

The author acknowledges South China Normal University for supporting this work.

References

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ISSN: 2056-9890
Volume 68| Part 10| October 2012| Page m1246
https://doi.org/10.1107/S1600536812037579
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