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ISSN: 2056-9890

Bis(guanidinium) trans-di­aqua­bis­(malonato-κ2O,O′)cobaltate(II)

aDorna Institute of Science, No. 83 Padadshahr, 14 St. Ahwaz, Khozestan, Iran, and bFaculty of Chemistry, University of Wrocław, 14 Joliot-Curie St., 50-383 Wrocław, Poland
*Correspondence e-mail: holynska@wcheto.chem.uni.wroc.pl

(Received 20 November 2007; accepted 1 December 2007; online 18 December 2007)

In the title compound, (CH6N3)2[Co(C3H2O4)2(H2O)2], the anions lie on crystallographic centres of inversion. The crystal structure adopts a layered structure, stabilized by an extensive network of N—H⋯O and O—H⋯O hydrogen bonds. One H atom of the guanidinium cation does not participate in any strong hydrogen bonds.

Related literature

For related literature, see: Cygler et al. (1976[Cygler, M., Grabowski, M. J., Stępień, A. & Wajsman, E. (1976). Acta Cryst. B32, 2391-2395.]); Etter et al. (1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]); Hemamalini et al. (2006[Hemamalini, M., Muthiah, P. T., Butcher, R. J. & Lynch, D. E. (2006). Inorg. Chem. Commun. 9, 1155-1160.]); Videnova-Adrabińska et al. (2007[Videnova-Adrabińska, V., Obara, E. & Lis, T. (2007). New J. Chem. 31, 287-295.]); Zhao et al. (2007[Zhao, X.-J., Zhang, Z.-H., Wang, Y. & Du, M. (2007). Inorg. Chim. Acta, 360, 1921-1928.]).

[Scheme 1]

Experimental

Crystal data
  • (CH6N3)2[Co(C3H2O4)2(H2O)2]

  • Mr = 419.23

  • Monoclinic, P 21 /c

  • a = 8.969 (3) Å

  • b = 11.524 (4) Å

  • c = 8.272 (3) Å

  • β = 111.61 (4)°

  • V = 794.9 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 1.15 mm−1

  • T = 100 (2) K

  • 0.31 × 0.25 × 0.18 mm

Data collection
  • Oxford Diffraction Xcalibur PX CCD diffractometer

  • Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2006[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]) Tmin = 0.720, Tmax = 0.848

  • 11133 measured reflections

  • 3445 independent reflections

  • 2768 reflections with I > 2σ(I)

  • Rint = 0.024

Refinement
  • R[F2 > 2σ(F2)] = 0.031

  • wR(F2) = 0.091

  • S = 1.03

  • 3445 reflections

  • 115 parameters

  • H-atom parameters constrained

  • Δρmax = 0.58 e Å−3

  • Δρmin = −0.43 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N20—H201⋯O11 0.86 2.26 3.043 (2) 151
N20—H201⋯O1Wi 0.86 2.46 3.117 (2) 133
N10—H102⋯O21ii 0.86 2.14 2.984 (2) 168
N10—H101⋯O12iii 0.86 2.07 2.930 (2) 177
N30—H301⋯O22iii 0.86 1.99 2.841 (2) 168
N30—H302⋯O21 0.86 2.08 2.934 (2) 173
O1W—H1W⋯O22iv 0.82 1.85 2.633 (2) 160
O1W—H2W⋯O21v 0.82 2.04 2.835 (2) 162
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) [-x+2, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iii) x+1, y, z+1; (iv) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (v) [-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: CrysAlis CCD (Oxford Diffraction, 2006[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2006[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); molecular graphics: DIAMOND (Brandenburg & Putz, 2005[Brandenburg, K. & Putz, H. (2005). DIAMOND. Version 3. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Supramolecular motifs with malonate ions have been widely explored in crystal engineering (Hemamalini et al., 2006, Zhao et al., 2007). These ligands as part of [M(malonate)2(H2O)2]2- anions have been used as "robust anionic building blocks for crystal engineering of inorganic-organic hybrid materials" (Zhao et al., 2007).

The title compound consists of trans-diaquabis(malonato-O,O')-cobaltate(II) anions and guanidinium cations (Fig. 1). In each centrosymmetric anion, the central CoII atom is octahedrally surrounded by two water ligands and two chelating malonate ligands. The guanidinium cation geometrical parameters agree with those previously reported (Cygler et al., 1976).

The crystal adopts a layered structure, common for guanidinium salts (Fig. 2; Videnova-Adrabińska et al., 2007). Alternate layers consist of the trans-diaquabis(malonato-O,O')-cobaltate(II) anions and the guanidinium cations. Within each anion layer, both water ligands are involved in O—H···O hydrogen bonds. In two of these hydrogen bonds, the carboxyl O22 and O21 atoms from the malonate ligands act as acceptors (Fig. 3). Each guanidinium cation is hydrogen bonded to the anions from both neighbouring anion layers (Fig. 3). Atom H201 participates in a bifurcated N—H···O hydrogen bond to the malonate carboxyl O11 and water O1W atoms, constituting a R12(4) motif (Etter et al., 1990). Atom H302 is involved in the N30—H302···O21 hydrogen bond with the malonate carboxyl O21 atom. This hydrogen bond along with the N20—H201···O11 hydrogen bonds forms a R22(8) motif (Etter et al., 1990). The hydrogen bonds formed between the guanidinium cation and another anion layer are the following: N10—H102···O21, N10—H101···O12 and N30—H301···O22. The latter two form a R31(8) structural motif (Etter et al., 1990). It is interesting to note that one guanidinium H atom (H202) is not involved in any strong hydrogen bonds.

Related literature top

For related literature, see: Cygler et al. (1976); Etter et al. (1990); Hemamalini et al. (2006); Videnova-Adrabińska et al. (2007); Zhao et al. (2007).

Experimental top

The title complex was prepared by dissolving guanidinium carbonate (4 mmol, 720 mg) and malonic acid (2 mmol, 208 mg) in water (20 ml). The mixture was stirred for about 1 h at room temperature. Subsequently, Co(ClO4)2 (1 mmol, 366 mg) was added to the resulting solution and stirred for about 3 h at room temperature. The solution yielded crystals after 10 d.

Refinement top

The malonate H atoms were generated in their calculated positions. All remaining H atoms were found in difference Fourier maps and their positions were refined initially with the water O—H bond lengths and guanidinium N—H bond lengths restrained to be 0.820 (1) and 0.860 (1) Å, respectively. In the final stages of refinement, these H atoms were constrained to ride on their parent atoms (AFIX 3 instruction) with Uiso(H) = 1.2Ueq(parent atom).

Structure description top

Supramolecular motifs with malonate ions have been widely explored in crystal engineering (Hemamalini et al., 2006, Zhao et al., 2007). These ligands as part of [M(malonate)2(H2O)2]2- anions have been used as "robust anionic building blocks for crystal engineering of inorganic-organic hybrid materials" (Zhao et al., 2007).

The title compound consists of trans-diaquabis(malonato-O,O')-cobaltate(II) anions and guanidinium cations (Fig. 1). In each centrosymmetric anion, the central CoII atom is octahedrally surrounded by two water ligands and two chelating malonate ligands. The guanidinium cation geometrical parameters agree with those previously reported (Cygler et al., 1976).

The crystal adopts a layered structure, common for guanidinium salts (Fig. 2; Videnova-Adrabińska et al., 2007). Alternate layers consist of the trans-diaquabis(malonato-O,O')-cobaltate(II) anions and the guanidinium cations. Within each anion layer, both water ligands are involved in O—H···O hydrogen bonds. In two of these hydrogen bonds, the carboxyl O22 and O21 atoms from the malonate ligands act as acceptors (Fig. 3). Each guanidinium cation is hydrogen bonded to the anions from both neighbouring anion layers (Fig. 3). Atom H201 participates in a bifurcated N—H···O hydrogen bond to the malonate carboxyl O11 and water O1W atoms, constituting a R12(4) motif (Etter et al., 1990). Atom H302 is involved in the N30—H302···O21 hydrogen bond with the malonate carboxyl O21 atom. This hydrogen bond along with the N20—H201···O11 hydrogen bonds forms a R22(8) motif (Etter et al., 1990). The hydrogen bonds formed between the guanidinium cation and another anion layer are the following: N10—H102···O21, N10—H101···O12 and N30—H301···O22. The latter two form a R31(8) structural motif (Etter et al., 1990). It is interesting to note that one guanidinium H atom (H202) is not involved in any strong hydrogen bonds.

For related literature, see: Cygler et al. (1976); Etter et al. (1990); Hemamalini et al. (2006); Videnova-Adrabińska et al. (2007); Zhao et al. (2007).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with displacement ellipsoids at 30% probability for non-H atoms. The part indicated with dashed lines is generated by the symmetry operation -x + 1, -y + 1, -z + 1.
[Figure 2] Fig. 2. View of the crystal structure along [010] showing cation and anion layers parallel to the bc plane.
[Figure 3] Fig. 3. View of the hydrogen bonding scheme. The non-aqueous H atoms not participating in any hydrogen bonds have been omitted and the neighbouring ions have been denoted with different colour (gray and black). The hydrogen bonds are indicated with dashed lines. Symmetry operations: (i) -x + 1, -y + 1, -z + 1; (ii) -x + 2, y - 1/2, -z + 3/2; (iii) x + 1, y, z + 1; (iv) x, -y + 3/2, z + 1/2; (v) -x + 1, y - 1/2, -z + 3/2.
Bis(guanidinium) trans-diaquabis(malonato-κ2O,O')cobaltate(II) top
Crystal data top
(CH6N3)2[Co(C3H2O4)2(H2O)2]F(000) = 434
Mr = 419.23Dx = 1.752 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 9403 reflections
a = 8.969 (3) Åθ = 2–35°
b = 11.524 (4) ŵ = 1.15 mm1
c = 8.272 (3) ÅT = 100 K
β = 111.61 (4)°Block, pink
V = 794.9 (5) Å30.31 × 0.25 × 0.18 mm
Z = 2
Data collection top
Oxford Diffraction XcaliburPX CCD
diffractometer
3445 independent reflections
Radiation source: sealed tube2768 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
ω & φ scansθmax = 36.5°, θmin = 3.0°
Absorption correction: analytical
(CrysAlis RED; Oxford Diffraction, 2006)
h = 1414
Tmin = 0.720, Tmax = 0.848k = 1517
11133 measured reflectionsl = 1313
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)] = 0.031Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.091H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.060P)2]
where P = (Fo2 + 2Fc2)/3
3445 reflections(Δ/σ)max < 0.001
115 parametersΔρmax = 0.58 e Å3
0 restraintsΔρmin = 0.43 e Å3
Crystal data top
(CH6N3)2[Co(C3H2O4)2(H2O)2]V = 794.9 (5) Å3
Mr = 419.23Z = 2
Monoclinic, P21/cMo Kα radiation
a = 8.969 (3) ŵ = 1.15 mm1
b = 11.524 (4) ÅT = 100 K
c = 8.272 (3) Å0.31 × 0.25 × 0.18 mm
β = 111.61 (4)°
Data collection top
Oxford Diffraction XcaliburPX CCD
diffractometer
3445 independent reflections
Absorption correction: analytical
(CrysAlis RED; Oxford Diffraction, 2006)
2768 reflections with I > 2σ(I)
Tmin = 0.720, Tmax = 0.848Rint = 0.024
11133 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0310 restraints
wR(F2) = 0.091H-atom parameters constrained
S = 1.03Δρmax = 0.58 e Å3
3445 reflectionsΔρmin = 0.43 e Å3
115 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Co0.50000.50000.50000.00962 (6)
O110.63731 (9)0.63701 (7)0.64141 (10)0.01133 (14)
O210.73793 (9)0.81502 (7)0.69642 (10)0.01402 (15)
O120.36319 (9)0.61700 (7)0.32127 (10)0.01255 (15)
O220.26743 (9)0.78487 (7)0.19808 (10)0.01408 (16)
N101.18921 (11)0.52517 (9)0.97198 (13)0.01332 (17)
H1011.23990.54981.07590.016*
H1021.21230.45950.93800.016*
N200.96719 (12)0.53173 (10)0.71656 (13)0.01675 (19)
H2010.87220.55620.65690.020*
H2020.98050.46050.69470.020*
N301.01516 (11)0.68018 (9)0.91834 (13)0.01470 (17)
H3011.08150.71331.00960.018*
H3020.93140.71470.84780.018*
C20.49632 (12)0.79769 (10)0.45438 (14)0.01213 (19)
H10.54730.84660.39090.015*
H20.43930.85120.50550.015*
O1W0.33221 (11)0.50357 (6)0.62312 (12)0.01377 (16)
H1W0.31460.56200.66960.017*
H2W0.32530.45670.69470.017*
C30.36771 (11)0.72673 (9)0.31750 (13)0.00952 (17)
C101.05660 (12)0.57952 (10)0.86977 (13)0.01182 (18)
C10.63218 (11)0.74416 (9)0.60624 (13)0.00945 (17)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co0.01041 (10)0.00690 (11)0.01022 (10)0.00018 (6)0.00225 (7)0.00026 (6)
O110.0121 (3)0.0070 (4)0.0123 (3)0.0000 (2)0.0014 (2)0.0010 (3)
O210.0127 (3)0.0093 (4)0.0154 (4)0.0015 (3)0.0004 (3)0.0020 (3)
O120.0138 (3)0.0070 (4)0.0124 (3)0.0008 (3)0.0003 (3)0.0009 (3)
O220.0134 (3)0.0086 (4)0.0144 (4)0.0002 (3)0.0017 (3)0.0021 (3)
N100.0120 (4)0.0128 (4)0.0128 (4)0.0013 (3)0.0018 (3)0.0006 (3)
N200.0125 (4)0.0190 (5)0.0153 (4)0.0012 (3)0.0011 (3)0.0049 (4)
N300.0111 (4)0.0136 (4)0.0158 (4)0.0014 (3)0.0008 (3)0.0014 (3)
O1W0.0200 (4)0.0074 (4)0.0180 (4)0.0006 (3)0.0118 (3)0.0001 (3)
C10.0094 (4)0.0088 (5)0.0102 (4)0.0004 (3)0.0037 (3)0.0012 (3)
C20.0126 (4)0.0082 (5)0.0119 (4)0.0008 (3)0.0002 (3)0.0002 (3)
C30.0096 (4)0.0082 (5)0.0101 (4)0.0003 (3)0.0029 (3)0.0003 (3)
C100.0101 (4)0.0126 (5)0.0123 (4)0.0023 (3)0.0035 (3)0.0002 (3)
Geometric parameters (Å, º) top
Co—O112.078 (1)O11—C11.2655 (14)
Co—O122.043 (2)O21—C11.2656 (14)
Co—O1W2.105 (2)O12—C31.2659 (14)
N10—C101.334 (2)O22—C31.2567 (14)
N20—C101.343 (2)C2—C11.5218 (16)
N30—C101.325 (2)C2—C31.5229 (16)
Co—O12i2.0429 (11)C2—H10.99
Co—O11i2.0777 (10)C2—H20.99
Co—O1Wi2.1053 (11)
O12—Co—O1188.8 (1)O11i—Co—O1Wi95.39 (4)
O12—Co—O1W89.5 (1)O1W—Co—O1Wi180.0
O11—Co—O1W95.4 (1)C1—O11—Co130.40 (7)
N30—C10—N10120.2 (1)C3—O12—Co131.37 (7)
N30—C10—N20120.6 (1)C1—C2—C3123.57 (10)
N10—C10—N20119.2 (2)C1—C2—H1106.4
O12i—Co—O12180.0C3—C2—H1106.4
O12i—Co—O1191.18 (5)C1—C2—H2106.4
O12i—Co—O11i88.82 (5)C3—C2—H2106.4
O12—Co—O11i91.18 (5)H1—C2—H2106.5
O11—Co—O11i180.0O22—C3—O12122.12 (10)
O12i—Co—O1W90.50 (4)O22—C3—C2115.15 (10)
O11i—Co—O1W84.61 (4)O12—C3—C2122.72 (9)
O12i—Co—O1Wi89.50 (4)O11—C1—O21122.56 (10)
O12—Co—O1Wi90.50 (4)O11—C1—C2122.38 (9)
O11—Co—O1Wi84.61 (4)O21—C1—C2115.05 (10)
C3—C2—C1—O118.6 (2)O1Wi—Co—O12—C387.46 (10)
C3—C2—C1—O21172.6 (1)Co—O12—C3—O22176.83 (7)
O12i—Co—O11—C1174.90 (9)Co—O12—C3—C24.47 (15)
O12—Co—O11—C15.10 (9)C1—C2—C3—O22177.85 (10)
O1W—Co—O11—C194.49 (9)C1—C2—C3—O120.93 (16)
O1Wi—Co—O11—C185.51 (9)Co—O11—C1—O21170.78 (7)
O11i—Co—O12—C3177.14 (9)Co—O11—C1—C210.54 (14)
O1W—Co—O12—C392.54 (10)
Symmetry code: (i) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N20—H201···O110.862.263.043 (2)151
N20—H201···O1Wi0.862.463.117 (2)133
N10—H102···O21ii0.862.142.984 (2)168
N10—H101···O12iii0.862.072.930 (2)177
N30—H301···O22iii0.861.992.841 (2)168
N30—H302···O210.862.082.934 (2)173
O1W—H1W···O22iv0.821.852.633 (2)160
O1W—H2W···O21v0.822.042.835 (2)162
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+2, y1/2, z+3/2; (iii) x+1, y, z+1; (iv) x, y+3/2, z+1/2; (v) x+1, y1/2, z+3/2.

Experimental details

Crystal data
Chemical formula(CH6N3)2[Co(C3H2O4)2(H2O)2]
Mr419.23
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)8.969 (3), 11.524 (4), 8.272 (3)
β (°) 111.61 (4)
V3)794.9 (5)
Z2
Radiation typeMo Kα
µ (mm1)1.15
Crystal size (mm)0.31 × 0.25 × 0.18
Data collection
DiffractometerOxford Diffraction XcaliburPX CCD
Absorption correctionAnalytical
(CrysAlis RED; Oxford Diffraction, 2006)
Tmin, Tmax0.720, 0.848
No. of measured, independent and
observed [I > 2σ(I)] reflections
11133, 3445, 2768
Rint0.024
(sin θ/λ)max1)0.838
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.031, 0.091, 1.03
No. of reflections3445
No. of parameters115
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.58, 0.43

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), DIAMOND (Brandenburg & Putz, 2005).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N20—H201···O110.862.263.043 (2)151
N20—H201···O1Wi0.862.463.117 (2)133
N10—H102···O21ii0.862.142.984 (2)168
N10—H101···O12iii0.862.072.930 (2)177
N30—H301···O22iii0.861.992.841 (2)168
N30—H302···O210.862.082.934 (2)173
O1W—H1W···O22iv0.821.852.633 (2)160
O1W—H2W···O21v0.822.042.835 (2)162
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+2, y1/2, z+3/2; (iii) x+1, y, z+1; (iv) x, y+3/2, z+1/2; (v) x+1, y1/2, z+3/2.
 

References

First citationBrandenburg, K. & Putz, H. (2005). DIAMOND. Version 3. Crystal Impact GbR, Bonn, Germany.  Google Scholar
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First citationEtter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256–262.  CrossRef CAS Web of Science IUCr Journals Google Scholar
First citationHemamalini, M., Muthiah, P. T., Butcher, R. J. & Lynch, D. E. (2006). Inorg. Chem. Commun. 9, 1155–1160.  Web of Science CSD CrossRef CAS Google Scholar
First citationOxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.  Google Scholar
First citationSheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.  Google Scholar
First citationVidenova-Adrabińska, V., Obara, E. & Lis, T. (2007). New J. Chem. 31, 287–295.  CSD CrossRef Google Scholar
First citationZhao, X.-J., Zhang, Z.-H., Wang, Y. & Du, M. (2007). Inorg. Chim. Acta, 360, 1921–1928.  Web of Science CSD CrossRef CAS Google Scholar

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