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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 65| Part 8| August 2009| Pages m1009-m1010

Di­aqua­bis­(5-carb­­oxy-1H-pyrazole-3-carboxyl­ato-κ2N2,O3)cobalt(II) dihydrate

aSchool of Science, Xi'an University of Architecture & Technology, Xi'an 710055, People's Republic of China, and bTianjin Medical University, Tianjin 300070, People's Republic of China
*Correspondence e-mail: xhd02@mails.thu.edu.cn

(Received 18 July 2009; accepted 23 July 2009; online 31 July 2009)

In the title complex, [Co(C5H3N2O4)2(H2O)2]·2H2O, the CoII ion lies on an inversion center and is coordinated in a distorted octa­hedral environment. In the crystal structure, complex and water mol­ecules are linked into a three-dimensional network by O—H⋯O and N—H⋯O hydrogen bonds.

Related literature

For a mononuclear zinc(II) complex with a pyrazole-3,5-dicarboxyl­ato ligand, see: Xie et al. (2006[Xie, H.-D., Xie, C.-Z., Wang, X.-Q., Shen, G.-Q. & Shen, D.-Z. (2006). Acta Cryst. E62, m3119-m3121.]) and for a cobalt(III) complex with a 5-carb­oxy-1H-pyrazole-3-carboxyl­ato ligand, see: Xie et al. (2007[Xie, H.-D., Xie, C.-Z., Wang, X.-Q., Shen, G.-Q. & Shen, D.-Z. (2007). Acta Cryst. E63, m1477-m1479.]). The 3,5-pyrazole­dicarboxylic acid ligand is asymmetric and has six potential coordination sites which can act to link together metal centers through a number of bridging modes, see: King et al. (2004[King, P., Clerac, R., Anson, C. E. & Powell, A. K. (2004). Dalton Trans. pp. 852-861.]). A variety of complexes containing this ligand have been reported, see: Frisch & Cahill (2005[Frisch, M. & Cahill, C. L. (2005). Dalton Trans. pp. 1518-1523.]); King et al. (2003[King, P., Clerac, R., Anson, C. E., Coulon, C. & Powell, A. K. (2003). Inorg. Chem. 42, 3492-3500.], 2004[King, P., Clerac, R., Anson, C. E. & Powell, A. K. (2004). Dalton Trans. pp. 852-861.]); Li et al. (2005[Li, X.-H., Lei, X.-X., Tian, Y.-G. & Wang, S. (2005). Acta Cryst. E61, m702-m704.]); Pan, Ching et al. (2001[Pan, L., Ching, N., Huang, X.-Y. & Li, J. (2001). Chem. Eur. J. 7, 4431-4437.]); Pan, Frydel et al. (2001[Pan, L., Frydel, T., Sander, M. B., Huang, X.-Y. & Li, J. (2001). Inorg. Chem. 40, 1271-1283.]).

[Scheme 1]

Experimental

Crystal data
  • [Co(C5H3N2O4)2(H2O)2]·2H2O

  • Mr = 441.18

  • Monoclinic, P 21 /c

  • a = 10.030 (3) Å

  • b = 12.483 (4) Å

  • c = 6.827 (2) Å

  • β = 108.641 (4)°

  • V = 809.9 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 1.14 mm−1

  • T = 291 K

  • 0.32 × 0.27 × 0.14 mm

Data collection
  • Bruker SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.713, Tmax = 0.854

  • 5748 measured reflections

  • 1502 independent reflections

  • 1331 reflections with I > 2σ(I)

  • Rint = 0.036

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.142

  • S = 1.12

  • 1502 reflections

  • 129 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.84 e Å−3

  • Δρmin = −0.44 e Å−3

Table 1
Selected geometric parameters (Å, °)

Co1—O5 2.065 (3)
Co1—N1 2.108 (3)
Co1—O1 2.120 (3)
O1—C1 1.262 (5)
O2—C1 1.256 (5)
O5i—Co1—O5 180
O5—Co1—N1 90.84 (12)
O5—Co1—N1i 89.16 (12)
N1—Co1—N1i 180
O5—Co1—O1i 91.18 (12)
N1—Co1—O1i 103.22 (11)
O5—Co1—O1 88.82 (12)
N1—Co1—O1 76.78 (11)
O1i—Co1—O1 180
Symmetry code: (i) -x+1, -y+2, -z.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O4—H4⋯O2ii 0.82 1.73 2.535 (4) 169
O5—H1W⋯O3iii 0.83 2.07 2.887 (4) 171
O5—H2W⋯O2iv 0.83 1.91 2.726 (4) 171
O6—H4W⋯O1v 0.85 (11) 2.06 (11) 2.828 (5) 149 (10)
O6—H3W⋯O3vi 0.84 2.30 2.932 (5) 132
N2—H2⋯O6vii 0.86 1.91 2.714 (5) 155
Symmetry codes: (ii) [-x+2, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) x-1, y, z; (iv) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (v) -x+1, -y+1, -z; (vi) [-x+2, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (vii) x, y+1, z.

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SMART 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

In the past few decades, self-assembly processes involving metal ions and organic ligands directed by either metal coordination or hydrogen bonds have received a great deal of attention in the field of supramolecular chemistry and crystal engineering. The 3,5-pyrazoledicarboxylic acid ligand is asymmetric and has six potential coordination sites which can act to link together metal centers through a number of bridging modes (King et al., 2004). A variety of complexes containing this ligand have been reported (Frisch et al., 2005; King et al., 2003, 2004; Pan, Ching et al., 2001; Pan, Frydel et al., 2001; Li et al., 2005).

The molecular structure of the title complex , (I), is shown in Fig. 1. The CoII ion is located on an inversion center and is coordinated in a distorted octahedral environment. The axial sites are occupied by water molecules and the equatorial plane is fromed by two oxygen donors and two nitrogen donors from two chelating 5-carboxy-pyrazole-3-carboxylato ligands. In the crystal structure complex and water molecules are linked into a three-dimensional network by O-H···O and N-H···O hydrogen bonds.

Related literature top

For a mononuclear zinc(II) complex with a pyrazole-3,5-dicarboxylato ligand, see: Xie et al. (2006) and for a cobalt(III) complex with a 5-carboxy-1H-pyrazole-3-carboxylato ligand, see: Xie et al. (2007). The 3,5-pyrazoledicarboxylic acid ligand is asymmetric and has six potential coordination sites which can act to link together metal centers through a number of bridging modes, see: King et al. (2004). A variety of complexes containing this ligand have been reported, see: Frisch & Cahill (2005); King et al. (2003, 2004); Li et al. (2005); Pan, Ching et al. (2001); Pan, Frydel et al. (2001).

Experimental top

A mixture of cobalt(II) nitrate (hexhydrate) (0.2 mmol, 58 mg), 3,5-pyrazoledicarboxylic acid (0.4 mmol, 62 mg) and H2O (18.0 ml) in a 1:2:5000 molar ratio was sealed in a 25 ml stainless steel reactor with a Teflon liner. The autoclave was kept at 423 K for 3 d, then cooled to room temperature at a rate of 4 K/h. Orange block-shaped crystals of the title complex were collected by filtration for the structural analysis.

Refinement top

All H atoms bonded to C and N atoms were initially located in difference Fourier maps but were subsequently refined in a riding-model approximation with C—H = 0.93 Å, N—H = 0.86 Å, Uiso(H) = 1.2Ueq(C,N). The O atoms bonded to the carboxylic group and the coordinated water atom were included in calculated positions and refined in a riding-model approximation with O-H = 0.82-0.83Å and Uiso(H) = 1.2-1.5Ueq(O). One of the solvent water H atoms was included with O-H = 0.84; Uiso(H) = 1.2Ueq(O) and the other H atom was refined isotropically.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); 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 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with atom labels and 35% probability displacement ellipsoids for non-H atoms [symmetry code: (A) -x+1, -y+2, -z]. Only the unique solvent water molecule is shown.
[Figure 2] Fig. 2. Part of the crystal structure of (I) showing the donor acceptor distances of hydrogen bonds as dashed lines. H atoms have been omitted for clarity.
Diaquabis(5-carboxy-1H-pyrazole-3-carboxylato- κ2N2,O3)cobalt(II) dihydrate top
Crystal data top
[Co(C5H3N2O4)2(H2O)2]·2H2OF(000) = 450
Mr = 441.18Dx = 1.809 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2747 reflections
a = 10.030 (3) Åθ = 2.7–27.9°
b = 12.483 (4) ŵ = 1.14 mm1
c = 6.827 (2) ÅT = 291 K
β = 108.641 (4)°Block, orange
V = 809.9 (5) Å30.32 × 0.27 × 0.14 mm
Z = 2
Data collection top
Bruker SMART CCD
diffractometer
1502 independent reflections
Radiation source: fine-focus sealed tube1331 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.036
ϕ and ω scansθmax = 25.5°, θmin = 2.7°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1212
Tmin = 0.713, Tmax = 0.854k = 1515
5748 measured reflectionsl = 88
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)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.142H atoms treated by a mixture of independent and constrained refinement
S = 1.12 w = 1/[σ2(Fo2) + (0.0775P)2 + 1.4115P]
where P = (Fo2 + 2Fc2)/3
1502 reflections(Δ/σ)max < 0.001
129 parametersΔρmax = 0.84 e Å3
0 restraintsΔρmin = 0.44 e Å3
Crystal data top
[Co(C5H3N2O4)2(H2O)2]·2H2OV = 809.9 (5) Å3
Mr = 441.18Z = 2
Monoclinic, P21/cMo Kα radiation
a = 10.030 (3) ŵ = 1.14 mm1
b = 12.483 (4) ÅT = 291 K
c = 6.827 (2) Å0.32 × 0.27 × 0.14 mm
β = 108.641 (4)°
Data collection top
Bruker SMART CCD
diffractometer
1502 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1331 reflections with I > 2σ(I)
Tmin = 0.713, Tmax = 0.854Rint = 0.036
5748 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0480 restraints
wR(F2) = 0.142H atoms treated by a mixture of independent and constrained refinement
S = 1.12Δρmax = 0.84 e Å3
1502 reflectionsΔρmin = 0.44 e Å3
129 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 > σ(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
Co10.50001.00000.00000.0227 (3)
O10.5183 (3)0.8358 (2)0.0667 (5)0.0308 (6)
O20.6657 (3)0.6977 (2)0.0142 (5)0.0337 (7)
O31.1998 (3)0.9569 (3)0.3134 (5)0.0408 (8)
O41.0960 (3)1.1105 (2)0.3529 (5)0.0366 (7)
H41.17721.13240.39770.055*
O50.4797 (3)0.9554 (3)0.2803 (5)0.0378 (7)
H1W0.40310.95940.30200.045*
H2W0.52960.90690.34840.045*
O60.7621 (4)0.2301 (3)0.2670 (8)0.0684 (13)
H3W0.76170.29260.31160.082*
N10.7187 (3)0.9727 (3)0.1137 (5)0.0238 (7)
N20.8371 (3)1.0290 (2)0.1925 (5)0.0237 (7)
H20.84021.09580.22510.028*
C10.6402 (4)0.7957 (3)0.0049 (6)0.0239 (8)
C20.7586 (4)0.8723 (3)0.0850 (6)0.0232 (7)
C30.9054 (4)0.8646 (3)0.1462 (6)0.0255 (8)
H30.95950.80470.14220.031*
C40.9519 (4)0.9668 (3)0.2143 (6)0.0246 (8)
C51.0964 (4)1.0103 (3)0.2981 (6)0.0264 (8)
H4W0.678 (12)0.232 (9)0.182 (18)0.19 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0135 (4)0.0169 (4)0.0356 (4)0.0024 (2)0.0049 (3)0.0001 (3)
O10.0156 (13)0.0203 (13)0.0522 (17)0.0011 (10)0.0046 (11)0.0035 (12)
O20.0203 (14)0.0210 (14)0.0535 (18)0.0006 (10)0.0031 (12)0.0062 (12)
O30.0198 (15)0.0342 (16)0.066 (2)0.0006 (12)0.0106 (14)0.0041 (15)
O40.0207 (14)0.0269 (15)0.0568 (19)0.0042 (11)0.0048 (13)0.0063 (13)
O50.0292 (16)0.0418 (17)0.0443 (16)0.0129 (13)0.0143 (13)0.0130 (14)
O60.041 (2)0.0318 (19)0.124 (4)0.0026 (15)0.014 (2)0.010 (2)
N10.0136 (15)0.0210 (15)0.0344 (17)0.0010 (12)0.0041 (12)0.0024 (12)
N20.0159 (15)0.0154 (14)0.0379 (17)0.0022 (12)0.0059 (13)0.0025 (13)
C10.0170 (17)0.0197 (18)0.0327 (19)0.0005 (14)0.0047 (15)0.0014 (14)
C20.0167 (17)0.0185 (17)0.0329 (19)0.0012 (14)0.0056 (15)0.0014 (14)
C30.0171 (17)0.0183 (18)0.039 (2)0.0018 (13)0.0066 (15)0.0005 (15)
C40.0154 (17)0.0236 (18)0.0336 (19)0.0010 (14)0.0064 (14)0.0008 (15)
C50.0205 (19)0.0238 (19)0.033 (2)0.0021 (14)0.0065 (16)0.0010 (15)
Geometric parameters (Å, º) top
Co1—O5i2.065 (3)O5—H2W0.8277
Co1—O52.065 (3)O6—H3W0.8380
Co1—N12.108 (3)O6—H4W0.85 (11)
Co1—N1i2.108 (3)N1—N21.336 (4)
Co1—O1i2.120 (3)N1—C21.349 (5)
Co1—O12.120 (3)N2—C41.358 (5)
O1—C11.262 (5)N2—H20.8600
O2—C11.256 (5)C1—C21.495 (5)
O3—C51.209 (5)C2—C31.400 (5)
O4—C51.306 (5)C3—C41.386 (5)
O4—H40.8200C3—H30.9300
O5—H1W0.8288C4—C51.481 (5)
O5i—Co1—O5180N2—N1—C2106.3 (3)
O5i—Co1—N189.16 (12)N2—N1—Co1138.6 (3)
O5—Co1—N190.84 (12)C2—N1—Co1114.8 (2)
O5i—Co1—N1i90.84 (12)N1—N2—C4110.9 (3)
O5—Co1—N1i89.16 (12)N1—N2—H2124.6
N1—Co1—N1i180C4—N2—H2124.6
O5i—Co1—O1i88.82 (12)O2—C1—O1124.1 (3)
O5—Co1—O1i91.18 (12)O2—C1—C2119.7 (3)
N1—Co1—O1i103.22 (11)O1—C1—C2116.2 (3)
N1i—Co1—O1i76.78 (11)N1—C2—C3110.7 (3)
O5i—Co1—O191.18 (12)N1—C2—C1114.8 (3)
O5—Co1—O188.82 (12)C3—C2—C1134.5 (3)
N1—Co1—O176.78 (11)C4—C3—C2104.3 (3)
N1i—Co1—O1103.22 (11)C4—C3—H3127.9
O1i—Co1—O1180C2—C3—H3127.9
C1—O1—Co1116.9 (2)N2—C4—C3107.9 (3)
C5—O4—H4109.5N2—C4—C5121.6 (3)
Co1—O5—H1W121.4C3—C4—C5130.6 (3)
Co1—O5—H2W119.8O3—C5—O4125.8 (4)
H1W—O5—H2W111.9O3—C5—C4122.5 (3)
H3W—O6—H4W95.7O4—C5—C4111.7 (3)
O5i—Co1—O1—C192.3 (3)Co1—N1—C2—C3174.1 (3)
O5—Co1—O1—C187.7 (3)N2—N1—C2—C1179.5 (3)
N1—Co1—O1—C13.4 (3)Co1—N1—C2—C15.3 (4)
N1i—Co1—O1—C1176.6 (3)O2—C1—C2—N1171.3 (4)
O5i—Co1—N1—N281.6 (4)O1—C1—C2—N18.3 (5)
O5—Co1—N1—N298.4 (4)O2—C1—C2—C39.5 (7)
O1i—Co1—N1—N26.9 (4)O1—C1—C2—C3170.8 (4)
O1—Co1—N1—N2173.1 (4)N1—C2—C3—C40.1 (4)
O5i—Co1—N1—C290.0 (3)C1—C2—C3—C4179.3 (4)
O5—Co1—N1—C290.0 (3)N1—N2—C4—C30.1 (4)
O1i—Co1—N1—C2178.6 (3)N1—N2—C4—C5179.8 (3)
O1—Co1—N1—C21.4 (3)C2—C3—C4—N20.0 (4)
C2—N1—N2—C40.2 (4)C2—C3—C4—C5179.9 (4)
Co1—N1—N2—C4171.9 (3)N2—C4—C5—O3178.0 (4)
Co1—O1—C1—O2172.5 (3)C3—C4—C5—O31.9 (7)
Co1—O1—C1—C27.2 (4)N2—C4—C5—O42.7 (5)
N2—N1—C2—C30.2 (4)C3—C4—C5—O4177.4 (4)
Symmetry code: (i) x+1, y+2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H4···O2ii0.821.732.535 (4)169
O5—H1W···O3iii0.832.072.887 (4)171
O5—H2W···O2iv0.831.912.726 (4)171
O6—H4W···O1v0.85 (11)2.06 (11)2.828 (5)149 (10)
O6—H3W···O3vi0.842.302.932 (5)132
N2—H2···O6vii0.861.912.714 (5)155
Symmetry codes: (ii) x+2, y+1/2, z+1/2; (iii) x1, y, z; (iv) x, y+3/2, z+1/2; (v) x+1, y+1, z; (vi) x+2, y1/2, z+1/2; (vii) x, y+1, z.

Experimental details

Crystal data
Chemical formula[Co(C5H3N2O4)2(H2O)2]·2H2O
Mr441.18
Crystal system, space groupMonoclinic, P21/c
Temperature (K)291
a, b, c (Å)10.030 (3), 12.483 (4), 6.827 (2)
β (°) 108.641 (4)
V3)809.9 (5)
Z2
Radiation typeMo Kα
µ (mm1)1.14
Crystal size (mm)0.32 × 0.27 × 0.14
Data collection
DiffractometerBruker SMART CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.713, 0.854
No. of measured, independent and
observed [I > 2σ(I)] reflections
5748, 1502, 1331
Rint0.036
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.142, 1.12
No. of reflections1502
No. of parameters129
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.84, 0.44

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top
Co1—O52.065 (3)O1—C11.262 (5)
Co1—N12.108 (3)O2—C11.256 (5)
Co1—O12.120 (3)
O5i—Co1—O5180N1—Co1—O1i103.22 (11)
O5—Co1—N190.84 (12)O5—Co1—O188.82 (12)
O5—Co1—N1i89.16 (12)N1—Co1—O176.78 (11)
N1—Co1—N1i180O1i—Co1—O1180
O5—Co1—O1i91.18 (12)
Symmetry code: (i) x+1, y+2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H4···O2ii0.821.732.535 (4)168.9
O5—H1W···O3iii0.832.072.887 (4)171.1
O5—H2W···O2iv0.831.912.726 (4)171.0
O6—H4W···O1v0.85 (11)2.06 (11)2.828 (5)149 (10)
O6—H3W···O3vi0.842.302.932 (5)132.4
N2—H2···O6vii0.861.912.714 (5)155.0
Symmetry codes: (ii) x+2, y+1/2, z+1/2; (iii) x1, y, z; (iv) x, y+3/2, z+1/2; (v) x+1, y+1, z; (vi) x+2, y1/2, z+1/2; (vii) x, y+1, z.
 

Acknowledgements

The authors thank the University Youth Fund (grant No. RC0735) for financial support.

References

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Volume 65| Part 8| August 2009| Pages m1009-m1010
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