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Acta Crystallogr Sect E Struct Rep Online. 2009 September 1; 65(Pt 9): m1130–m1131.
Published online 2009 August 26. doi:  10.1107/S1600536809033200
PMCID: PMC2969956

Tetra­aqua­bis(isonicotinamide-κN 1)cobalt(II) bis­(4-formyl­benzoate) dihydrate

Abstract

The asymmetric unit of the crystal structure of the title complex, [Co(C6H6N2O)2(H2O)4](C8H5O3)2·2H2O, contains one-half of the complex cation with the CoII ion located on an inversion center, a 4-formyl­benzoate (FB) counter-anion and an uncoordinated water mol­ecule. The four O atoms in the equatorial plane around the CoII ion form a slightly distorted square-planar arrangement with an average Co—O bond length of 2.086 Å; the slightly distorted octa­hedral coordination is completed by the two N atoms of the isonicotinamide (INA) ligands at a slightly longer distance [2.1603 (14) Å] in the axial positions. The dihedral angle between the carboxyl­ate group and the attached benzene ring is 5.93 (13)°, while the pyridine and benzene rings are oriented at a dihedral angle of 3.09 (6)°. In the crystal structure, O—H(...)O, N—H(...)O and C—H(...)O hydrogen bonds link the mol­ecules into a three-dimensional network. π–π Contacts between the benzene and pyridine rings [centroid–centroid distance = 3.758 (1) Å] may further stabilize the crystal structure.

Related literature

For general background to transition metal complexes of nicotinamide and/or the nicotinic acid derivative N,N-diethyl­nicotinamide, see: Bigoli et al. (1972 [triangle]); Krishnamachari (1974 [triangle]). For related structures, see: Hökelek et al. (2009 [triangle]); Sertçelik et al. (2009 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-m1130-scheme1.jpg

Experimental

Crystal data

  • [Co(C6H6N2O)2(H2O)4](C8H5O3)2·2H2O
  • M r = 709.53
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-m1130-efi1.jpg
  • a = 6.4490 (2) Å
  • b = 6.8836 (3) Å
  • c = 18.1792 (5) Å
  • α = 81.967 (3)°
  • β = 84.681 (3)°
  • γ = 72.564 (2)°
  • V = 761.28 (5) Å3
  • Z = 1
  • Mo Kα radiation
  • μ = 0.64 mm−1
  • T = 100 K
  • 0.17 × 0.08 × 0.04 mm

Data collection

  • Bruker Kappa APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.943, T max = 0.978
  • 13740 measured reflections
  • 3780 independent reflections
  • 2884 reflections with I > 2σ(I)
  • R int = 0.054

Refinement

  • R[F 2 > 2σ(F 2)] = 0.034
  • wR(F 2) = 0.074
  • S = 0.98
  • 3780 reflections
  • 236 parameters
  • 9 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.36 e Å−3
  • Δρmin = −0.41 e Å−3

Data collection: APEX2 (Bruker, 2007 [triangle]); cell refinement: SAINT (Bruker, 2007 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: Mercury (Macrae et al., 2006 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]) and PLATON (Spek, 2009 [triangle]).

Table 1
Selected bond lengths (Å)
Table 2
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809033200/xu2594sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809033200/xu2594Isup2.hkl

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

Acknowledgments

The authors are indebted to Anadolu University and the Medicinal Plants and Medicine Research Centre of Anadolu University, Eskişehir, Turkey, for the use of the X-ray diffractometer. This work was supported financially by Kafkas University Research Fund (grant No. 2009-FEF-03).

supplementary crystallographic information

Comment

As a part of our ongoing investigation on transition metal complexes of nicotinamide (NA), one form of niacin (Krishnamachari, 1974), and/or the nicotinic acid derivative N,N-diethylnicotinamide (DENA), an important respiratory stimulant (Bigoli et al., 1972), the title compound was synthesized and its crystal structure is reported herein.

The title compound is a monomeric complex, with CoII ion on a centre of symmetry, consisting of two INA ligands, four coordinated water molecules, two FB anions and two uncoordinated water molecules. The structures of some DENA and/or INA complexes of CoII ion, [Co(C8H5O3)2(C10H14N2O)2(H2O)2] (Sertçelik et al., 2009) and [Co(C6H6N2O)(C9H10NO2)2(H2O)2] (Hökelek et al., 2009) have also been determined.

In the title compound, INA ligands are monodentate. The four O atoms (O5, O6, and the symmetry-related atoms, O5', O6') in the equatorial plane around the Co atom form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination is completed by the two pyridine N atoms (N1, N1') of the INA ligands at 2.1603 (14) Å from the Co atom in the axial positions (Table 1, Fig. 1). The average Co—O bond length is 2.0861 (13) Å. The O—H···O hydrogen bond (Table 2) links the coordinated water molecule to the FB anion. The dihedral angle between the planar carboxylate group (O1/O2/C1) and the benzene ring A (C2—C7) is 5.93 (13)°, while that between rings A and B (N1/C8—C12) is 3.09 (6)°.

In the crystal structure, O—H···O, N—H···O and C—H···O hydrogen bonds (Table 2) link the molecules into a three-dimensional network, in which they may be effective in the stabilization of the structure. The π–π contact between the benzene and pyridine rings, Cg1—Cg2, [where Cg1 and Cg2 are centroids of the rings A (C2—C7) and B (N1/C8—C12), respectively] may further stabilize the structure, with centroid-centroid distance of 3.758 (1) Å.

Experimental

The title compound was prepared by the reaction of CoSO4.7H2O (1.41 g, 5 mmol) in H2O (25 ml) and INA (1.22 g, 10 mmol) in H2O (40 ml) with sodium 4-formylbenzoate (1.72 g, 10 mmol) in H2O (50 ml). The mixture was filtered and set aside to crystallize at ambient temperature for several days, giving orange single crystals.

Refinement

Atoms H51, H52, H61, H62, H71 and H72 (for H2O) and H14 (for CH) were located in difference Fourier map and refined isotropically, with restrains of O5—H51 = 0.916 (13), O5—H52 = 0.865 (14), O6—H61 = 0.899 (13), O6—H62 = 0.871 (14), O7—H71 = 0.892 (14), O7—H72 = 0.935 (13) Å and H51—O5—H52 = 106.6 (16), H61—O6—H62 = 106.4 (16), H71—O7—H72 = 106.5 (15) °. The remaining H atoms were positioned geometrically with N—H = 0.86 Å (for NH2) and C—H = 0.93 Å, for aromatic H atoms and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C,N).

Figures

Fig. 1.
The structure of the title molecule with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Primed atoms are generated by the symmetry operator:(') -x, -y, -z. Dashed line indicates the hydrogen-bonding.

Crystal data

[Co(C6H6N2O)2(H2O)4](C8H5O3)2·2H2OZ = 1
Mr = 709.53F(000) = 369
Triclinic, P1Dx = 1.548 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.4490 (2) ÅCell parameters from 4050 reflections
b = 6.8836 (3) Åθ = 1.1–28.4°
c = 18.1792 (5) ŵ = 0.64 mm1
α = 81.967 (3)°T = 100 K
β = 84.681 (3)°Rod-shaped, orange
γ = 72.564 (2)°0.17 × 0.08 × 0.04 mm
V = 761.28 (5) Å3

Data collection

Bruker Kappa APEXII CCD area-detector diffractometer3780 independent reflections
Radiation source: fine-focus sealed tube2884 reflections with I > 2σ(I)
graphiteRint = 0.054
[var phi] and ω scansθmax = 28.4°, θmin = 1.1°
Absorption correction: multi-scan (SADABS; Bruker, 2005)h = −8→8
Tmin = 0.943, Tmax = 0.978k = −9→8
13740 measured reflectionsl = −24→24

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.074H atoms treated by a mixture of independent and constrained refinement
S = 0.98w = 1/[σ2(Fo2) + (0.0308P)2] where P = (Fo2 + 2Fc2)/3
3780 reflections(Δ/σ)max < 0.001
236 parametersΔρmax = 0.36 e Å3
9 restraintsΔρmin = −0.41 e Å3

Special details

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)

xyzUiso*/Ueq
Co10.00000.00000.00000.01071 (11)
O1−0.3206 (2)0.68183 (19)−0.08763 (7)0.0168 (3)
O20.0316 (2)0.55083 (19)−0.12091 (7)0.0154 (3)
O30.6316 (2)−0.2347 (2)0.31750 (7)0.0191 (3)
O4−0.5540 (2)0.7430 (2)−0.46372 (7)0.0249 (3)
O50.1816 (2)0.2025 (2)−0.02613 (7)0.0129 (3)
H510.226 (3)0.251 (3)0.0122 (9)0.015*
H520.122 (3)0.309 (2)−0.0568 (9)0.015*
O60.2398 (2)−0.2399 (2)−0.04719 (7)0.0154 (3)
H610.382 (2)−0.268 (3)−0.0613 (10)0.015*
H620.189 (3)−0.321 (3)−0.0685 (10)0.015*
O70.1474 (2)0.1218 (2)0.58230 (7)0.0212 (3)
H710.222 (3)0.165 (3)0.6122 (9)0.015*
H720.239 (3)−0.002 (2)0.5679 (10)0.015*
N10.1381 (2)−0.0933 (2)0.10768 (8)0.0118 (3)
N20.3064 (2)−0.1744 (2)0.38109 (8)0.0159 (4)
H2A0.3647−0.19010.42300.019*
H2B0.1675−0.14610.37960.019*
C1−0.1665 (3)0.6195 (3)−0.13455 (10)0.0133 (4)
C2−0.2240 (3)0.6309 (3)−0.21448 (10)0.0119 (4)
C3−0.0588 (3)0.5837 (3)−0.26939 (10)0.0149 (4)
H30.08590.5438−0.25700.018*
C4−0.1087 (3)0.5957 (3)−0.34277 (10)0.0164 (4)
H40.00230.5630−0.37950.020*
C5−0.3246 (3)0.6567 (3)−0.36142 (10)0.0150 (4)
C6−0.4913 (3)0.7031 (3)−0.30633 (10)0.0146 (4)
H6−0.63590.7427−0.31870.018*
C7−0.4407 (3)0.6900 (3)−0.23320 (10)0.0140 (4)
H7−0.55170.7206−0.19640.017*
C80.0137 (3)−0.0686 (3)0.17118 (10)0.0130 (4)
H8−0.1367−0.02790.16830.016*
C90.0981 (3)−0.1008 (3)0.24058 (10)0.0128 (4)
H90.0057−0.08070.28300.015*
C100.3216 (3)−0.1633 (3)0.24610 (10)0.0114 (4)
C110.4511 (3)−0.1974 (3)0.18124 (10)0.0137 (4)
H110.6018−0.24480.18300.016*
C120.3547 (3)−0.1602 (3)0.11403 (10)0.0146 (4)
H120.4440−0.18270.07100.018*
C130.4314 (3)−0.1941 (3)0.31843 (10)0.0132 (4)
C14−0.3744 (3)0.6684 (3)−0.43957 (11)0.0203 (5)
H14−0.251 (3)0.611 (3)−0.4732 (11)0.025 (6)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Co10.0088 (2)0.0147 (2)0.00937 (19)−0.00406 (16)−0.00113 (14)−0.00213 (14)
O10.0131 (7)0.0241 (8)0.0145 (7)−0.0058 (6)−0.0016 (5)−0.0053 (6)
O20.0110 (7)0.0181 (7)0.0175 (7)−0.0034 (6)−0.0053 (5)−0.0027 (6)
O30.0116 (7)0.0274 (8)0.0181 (7)−0.0028 (6)−0.0042 (6)−0.0068 (6)
O40.0248 (8)0.0311 (9)0.0159 (7)−0.0013 (7)−0.0082 (6)−0.0036 (6)
O50.0124 (7)0.0173 (7)0.0101 (7)−0.0054 (6)−0.0040 (5)−0.0007 (5)
O60.0100 (7)0.0195 (8)0.0186 (7)−0.0049 (6)0.0001 (6)−0.0078 (6)
O70.0157 (8)0.0304 (9)0.0191 (7)−0.0062 (7)−0.0028 (6)−0.0079 (6)
N10.0107 (8)0.0134 (8)0.0123 (8)−0.0047 (7)−0.0004 (6)−0.0021 (6)
N20.0137 (8)0.0243 (9)0.0106 (8)−0.0048 (7)−0.0051 (6)−0.0033 (7)
C10.0166 (10)0.0101 (10)0.0147 (9)−0.0058 (8)−0.0034 (8)−0.0011 (7)
C20.0132 (10)0.0095 (9)0.0138 (9)−0.0041 (8)−0.0028 (7)−0.0006 (7)
C30.0114 (10)0.0148 (10)0.0185 (10)−0.0031 (8)−0.0032 (8)−0.0024 (8)
C40.0154 (10)0.0163 (10)0.0155 (10)−0.0024 (8)0.0017 (8)−0.0020 (8)
C50.0193 (10)0.0133 (10)0.0126 (9)−0.0045 (8)−0.0025 (8)−0.0012 (8)
C60.0114 (10)0.0160 (10)0.0166 (10)−0.0033 (8)−0.0042 (8)−0.0018 (8)
C70.0138 (10)0.0132 (10)0.0146 (9)−0.0029 (8)−0.0001 (8)−0.0028 (8)
C80.0091 (9)0.0152 (10)0.0140 (9)−0.0023 (8)−0.0018 (7)−0.0015 (8)
C90.0122 (10)0.0160 (10)0.0104 (9)−0.0048 (8)0.0010 (7)−0.0022 (7)
C100.0141 (10)0.0085 (9)0.0127 (9)−0.0038 (8)−0.0039 (7)−0.0014 (7)
C110.0089 (9)0.0168 (10)0.0161 (10)−0.0040 (8)−0.0032 (7)−0.0021 (8)
C120.0108 (10)0.0190 (10)0.0136 (9)−0.0036 (8)0.0005 (7)−0.0028 (8)
C130.0147 (10)0.0112 (10)0.0143 (9)−0.0031 (8)−0.0035 (8)−0.0027 (7)
C140.0236 (12)0.0214 (11)0.0143 (10)−0.0039 (10)0.0002 (9)−0.0033 (9)

Geometric parameters (Å, °)

Co1—O52.0570 (13)C2—C31.387 (2)
Co1—O5i2.0570 (13)C3—C41.387 (2)
Co1—O62.1151 (12)C3—H30.9300
Co1—O6i2.1151 (12)C4—H40.9300
Co1—N12.1603 (14)C5—C41.388 (3)
Co1—N1i2.1603 (14)C5—C141.471 (3)
O1—C11.261 (2)C6—C51.394 (2)
O2—C11.257 (2)C6—C71.382 (2)
O3—C131.236 (2)C6—H60.9300
O4—C141.214 (2)C7—C21.394 (2)
O5—H510.916 (13)C7—H70.9300
O5—H520.865 (14)C8—H80.9300
O6—H610.899 (13)C9—C81.383 (2)
O6—H620.871 (14)C9—C101.384 (2)
O7—H710.892 (14)C9—H90.9300
O7—H720.935 (13)C10—C111.386 (2)
N1—C81.344 (2)C10—C131.510 (2)
N1—C121.344 (2)C11—C121.380 (2)
N2—C131.331 (2)C11—H110.9300
N2—H2A0.8600C12—H120.9300
N2—H2B0.8600C14—H140.976 (19)
C2—C11.518 (2)
O5—Co1—O5i180.00 (4)C4—C3—C2120.16 (17)
O5—Co1—O693.11 (5)C4—C3—H3119.9
O5i—Co1—O686.89 (5)C3—C4—C5119.95 (17)
O5—Co1—O6i86.89 (5)C3—C4—H4120.0
O5i—Co1—O6i93.11 (5)C5—C4—H4120.0
O5—Co1—N190.50 (5)C4—C5—C6120.09 (16)
O5i—Co1—N189.50 (5)C4—C5—C14119.15 (17)
O5—Co1—N1i89.50 (5)C6—C5—C14120.75 (17)
O5i—Co1—N1i90.50 (5)C5—C6—H6120.1
O6—Co1—O6i180.00 (9)C7—C6—C5119.78 (17)
O6—Co1—N191.81 (5)C7—C6—H6120.1
O6i—Co1—N188.19 (5)C2—C7—H7119.9
O6—Co1—N1i88.19 (5)C6—C7—C2120.21 (17)
O6i—Co1—N1i91.81 (5)C6—C7—H7119.9
N1i—Co1—N1180.00 (3)N1—C8—C9123.34 (16)
Co1—O5—H51118.1 (12)N1—C8—H8118.3
Co1—O5—H52114.2 (12)C9—C8—H8118.3
H51—O5—H52106.5 (16)C8—C9—C10119.24 (16)
Co1—O6—H61136.9 (12)C8—C9—H9120.4
Co1—O6—H62114.8 (12)C10—C9—H9120.4
H62—O6—H61106.4 (16)C9—C10—C11117.81 (16)
H71—O7—H72106.5 (15)C9—C10—C13123.74 (16)
C8—N1—Co1121.76 (12)C11—C10—C13118.44 (16)
C12—N1—Co1121.13 (12)C10—C11—H11120.3
C12—N1—C8116.80 (15)C12—C11—C10119.46 (17)
C13—N2—H2A120.0C12—C11—H11120.3
C13—N2—H2B120.0N1—C12—C11123.26 (16)
H2A—N2—H2B120.0N1—C12—H12118.4
O2—C1—O1125.45 (16)C11—C12—H12118.4
O2—C1—C2117.12 (16)O3—C13—N2122.54 (16)
O1—C1—C2117.42 (16)O3—C13—C10119.36 (16)
C3—C2—C1119.50 (16)N2—C13—C10118.09 (16)
C3—C2—C7119.82 (16)O4—C14—C5124.77 (19)
C7—C2—C1120.68 (16)O4—C14—H14119.5 (11)
C2—C3—H3119.9C5—C14—H14115.7 (11)
O5—Co1—N1—C8119.00 (13)C6—C5—C4—C3−0.9 (3)
O5i—Co1—N1—C8−61.00 (13)C14—C5—C4—C3−179.95 (17)
O5—Co1—N1—C12−54.41 (14)C4—C5—C14—O4−170.50 (19)
O5i—Co1—N1—C12125.59 (14)C6—C5—C14—O410.4 (3)
O6—Co1—N1—C8−147.87 (13)C7—C6—C5—C40.6 (3)
O6i—Co1—N1—C832.13 (13)C7—C6—C5—C14179.65 (17)
O6—Co1—N1—C1238.72 (14)C5—C6—C7—C20.1 (3)
O6i—Co1—N1—C12−141.28 (14)C6—C7—C2—C1178.94 (16)
Co1—N1—C8—C9−171.09 (13)C6—C7—C2—C3−0.5 (3)
C12—N1—C8—C92.6 (3)C10—C9—C8—N1−0.6 (3)
Co1—N1—C12—C11171.72 (14)C8—C9—C10—C11−2.1 (3)
C8—N1—C12—C11−2.0 (3)C8—C9—C10—C13177.26 (16)
C3—C2—C1—O1173.53 (16)C9—C10—C11—C122.6 (3)
C3—C2—C1—O2−5.6 (2)C13—C10—C11—C12−176.75 (16)
C7—C2—C1—O1−5.9 (3)C9—C10—C13—O3−174.44 (17)
C7—C2—C1—O2174.98 (16)C9—C10—C13—N25.0 (3)
C1—C2—C3—C4−179.23 (16)C11—C10—C13—O34.9 (3)
C7—C2—C3—C40.2 (3)C11—C10—C13—N2−175.59 (16)
C2—C3—C4—C50.5 (3)C10—C11—C12—N1−0.6 (3)

Symmetry codes: (i) −x, −y, −z.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N2—H2A···O4ii0.862.132.9680 (19)166
N2—H2B···O7iii0.862.052.8659 (19)158
O5—H51···O1iv0.92 (2)1.72 (2)2.6355 (18)175 (2)
O5—H52···O20.87 (2)1.86 (2)2.7236 (18)171 (2)
O6—H61···O1v0.90 (2)1.87 (2)2.7707 (19)177 (1)
O6—H62···O2vi0.87 (2)1.92 (2)2.7760 (19)168 (2)
O7—H71···O3vii0.89 (2)1.85 (2)2.7371 (19)174 (2)
O7—H72···O4ii0.94 (2)1.98 (2)2.9168 (19)177 (2)
C9—H9···O7iii0.932.563.458 (2)161
C12—H12···O5viii0.932.453.210 (2)139

Symmetry codes: (ii) x+1, y−1, z+1; (iii) −x, −y, −z+1; (iv) −x, −y+1, −z; (v) x+1, y−1, z; (vi) x, y−1, z; (vii) −x+1, −y, −z+1; (viii) −x+1, −y, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: XU2594).

References

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