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Acta Cryst. (2010). E66, m910-m911    [ doi:10.1107/S1600536810026462 ]

Diaquabis(4-methoxybenzoato-[kappa]O1)bis(nicotinamide-[kappa]N1)cobalt(II) dihydrate

T. Hökelek, H. Dal, B. Tercan, E. Tenlik and H. Necefoglu

Abstract top

In the mononuclear title compound, [Co(C8H7O3)2(C6H6N2O)2(H2O)2]·2H2O, the CoII ion is located on a crystallographic inversion center. The asymmetric unit is completed by one 4-methoxybenzoate anion, one nicotinamide (NA) ligand and one coordinated and one uncoordinated water molecule. All ligands act in a monodentate mode. The four O atoms in the equatorial plane around the CoII ion form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination is completed by the two pyridine N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxylate group and the attached benzene ring is 6.47 (7)°, while the pyridine and benzene rings are oriented at a dihedral angle of 72.80 (4)°. An O-H...O hydrogen bond links the uncoordinated water molecule to one of the carboxylate groups. In the crystal structure, intermolecular O-H...O, N-H...O and C-H...O hydrogen bonds link the molecules into a three-dimensional network.

Comment top

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, (I), is a mononuclear complex, where the CoII ion is located on a crystallographic inversion center. The asymmetric unit contains one 4-methoxybenzoate (PMOB) anion, one nicotinamide (NA) ligand and one coordinated and one uncoordinated water molecules, all ligands are monodentate (Fig. 1). The crystal structures of some NA and/or DENA complexes of CuII, CoII, NiII, MnII and ZnII ions, [Cu(C7H5O2)2(C10H14N2O)2], (II) (Hökelek et al., 1996), [Co(C6H6N2O)2(C7H4NO4)2(H2O)2], (III) (Hökelek & Necefoğlu, 1998), [Ni(C7H4ClO2)2(C6H6N2O)2(H2O)2], (IV) (Hökelek et al., 2009a), [Ni(C8H7O2)2(C6H6N2O)2(H2O)2], (V) (Necefoğlu et al., 2010), [Mn(C7H4ClO2)2(C10H14N2O)2(H2O)2], (VI) (Hökelek et al., 2009b) and [Zn(C7H4BrO2)2(C6H6N2O)2(H2O)2], (VII) (Hökelek et al., 2009c) have also been reported. In (II), two benzoate ions are coordinated to the Cu atom as bidentate ligands, while in other structures all ligands being monodentate.

The four O atoms (O1, O5, and the symmetry-related atoms, O1', O5') in the equatorial plane around the CoII ion form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination is completed by the two N atoms of the NA ligands (N1, N1') in the axial positions (Fig. 1). The near equality of the C1—O1 [1.2698 (14) Å] and C1—O2 [1.2626 (15) Å] bonds in the carboxylate group indicates a delocalized bonding arrangement, rather than localized single and double bonds. The average Co—O bond length is 2.0895 (9) Å, and the CoII ion is displaced out of the least-squares plane of the carboxylate group (O1/C1/O2) by 0.8407 (1) Å. The dihedral angle between the planar carboxylate group and the benzene ring A (C2—C7) is 6.47 (7)°, while that between rings A and B (N1/C9—C13) is 72.80 (4)°. An intramolecular O—H···O hydrogen bond (Table 1) links the uncoordinated water molecule to one of the carboxylate groups (Fig. 1).

In the crystal structure, intermolecular O—H···O, N—H···O and C—H···O hydrogen bonds (Table 1) link the molecules into a three-dimensional network.

Related literature top

For niacin, see: Krishnamachari (1974). For N,N-diethylnicotinamide, see: Bigoli et al. (1972). For related structures, see: Hökelek et al. (1996, 2009a,b,c); Hökelek & Necefoğlu (1998); Necefoğlu et al. (2010).

Experimental top

The title compound was prepared by the reaction of CoSO4.7H2O (2.81 g, 10 mmol) in H2O (50 ml) and nicotinamide (2.44 g, 20 mmol) in H2O (50 ml) with sodium 4-methoxybenzoate (3.48 g, 20 mmol) in H2O (100 ml). The mixture was filtered and set aside to crystallize at ambient temperature for one week, giving pink single crystals.

Refinement top

Atoms H21, H22 (for NH2) and H51, H52, H61, H62 (for H2O) were located in a difference Fourier map and refined isotropically. The remaining H atoms were positioned geometrically with C—H = 0.95 and 0.98 Å for aromatic and methyl H atoms and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.5 for methyl H and x = 1.2 for aromatic H atoms.

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: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound 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 lines indicate the hydrogen-bonding.
Diaquabis(4-methoxybenzoato-κO1)bis(nicotinamide-\ κN1)cobalt(II) dihydrate top
Crystal data top
[Co(C8H7O3)2(C6H6N2O)2(H2O)2]·2H2OZ = 1
Mr = 677.52F(000) = 353
Triclinic, P1Dx = 1.496 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.1568 (2) ÅCell parameters from 9220 reflections
b = 9.7502 (2) Åθ = 2.6–28.4°
c = 10.0700 (3) ŵ = 0.64 mm−1
α = 101.151 (3)°T = 100 K
β = 91.796 (2)°Block, pink
γ = 106.043 (3)°0.45 × 0.29 × 0.24 mm
V = 752.09 (4) Å3
Data collection top
Bruker Kappa APEXII CCD area-detector
diffractometer		3776 independent reflections
Radiation source: fine-focus sealed tube3541 reflections with I > 2σ(I)
graphiteRint = 0.023
φ and ω scansθmax = 28.5°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		h = −10→10
Tmin = 0.799, Tmax = 0.856k = −13→10
13470 measured reflectionsl = −13→13
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) = 0.074H atoms treated by a mixture of independent and constrained refinement
S = 1.07 w = 1/[σ2(Fo2) + (0.0387P)2 + 0.2836P]
where P = (Fo2 + 2Fc2)/3
3776 reflections(Δ/σ)max < 0.001
230 parametersΔρmax = 0.55 e Å−3
0 restraintsΔρmin = −0.31 e Å−3
Crystal data top
[Co(C8H7O3)2(C6H6N2O)2(H2O)2]·2H2Oγ = 106.043 (3)°
Mr = 677.52V = 752.09 (4) Å3
Triclinic, P1Z = 1
a = 8.1568 (2) ÅMo Kα radiation
b = 9.7502 (2) ŵ = 0.64 mm−1
c = 10.0700 (3) ÅT = 100 K
α = 101.151 (3)°0.45 × 0.29 × 0.24 mm
β = 91.796 (2)°
Data collection top
Bruker Kappa APEXII CCD area-detector
diffractometer		3776 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		3541 reflections with I > 2σ(I)
Tmin = 0.799, Tmax = 0.856Rint = 0.023
13470 measured reflectionsθmax = 28.5°
Refinement top
R[F2 > 2σ(F2)] = 0.027H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.074Δρmax = 0.55 e Å−3
S = 1.07Δρmin = −0.31 e Å−3
3776 reflectionsAbsolute structure: ?
230 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
Co10.00000.00000.00000.01140 (7)
O10.16134 (11)0.15267 (9)0.15761 (8)0.01516 (17)
O20.02618 (12)0.12855 (9)0.34523 (9)0.02010 (19)
O30.49079 (13)0.79361 (10)0.49240 (10)0.0241 (2)
O4−0.23377 (11)0.62299 (9)0.11798 (9)0.01950 (19)
O50.16105 (11)0.08580 (10)−0.14044 (9)0.01498 (17)
H510.180 (2)0.174 (2)−0.145 (2)0.038 (5)*
H520.118 (2)0.034 (2)−0.214 (2)0.034 (5)*
O60.10074 (14)−0.13088 (11)0.39872 (10)0.0230 (2)
H610.091 (3)−0.056 (3)0.380 (2)0.046 (6)*
H620.060 (3)−0.137 (2)0.474 (2)0.044 (6)*
N1−0.15075 (13)0.15172 (11)−0.00112 (10)0.01377 (19)
N2−0.00471 (14)0.58909 (12)0.22425 (11)0.0175 (2)
H210.028 (2)0.680 (2)0.2689 (18)0.029 (4)*
H220.050 (2)0.530 (2)0.2387 (17)0.024 (4)*
C10.13157 (15)0.20178 (12)0.27783 (11)0.0141 (2)
C20.22590 (15)0.35792 (12)0.33911 (12)0.0141 (2)
C30.35076 (16)0.43797 (14)0.26923 (12)0.0181 (2)
H30.37640.39230.18340.022*
C40.43723 (16)0.58247 (14)0.32337 (13)0.0203 (3)
H40.52290.63500.27550.024*
C50.39860 (16)0.65132 (13)0.44861 (13)0.0177 (2)
C60.27348 (17)0.57414 (14)0.51879 (13)0.0204 (3)
H60.24570.62070.60340.024*
C70.18914 (17)0.42784 (14)0.46397 (12)0.0187 (2)
H70.10500.37480.51270.022*
C80.4554 (2)0.87023 (15)0.61895 (14)0.0281 (3)
H8A0.52960.97100.63810.042*
H8B0.47700.82190.69170.042*
H8C0.33520.87030.61390.042*
C9−0.30977 (16)0.09903 (13)−0.06401 (13)0.0179 (2)
H9−0.3478−0.0009−0.10870.021*
C10−0.42123 (16)0.18327 (14)−0.06690 (14)0.0210 (3)
H10−0.53210.1423−0.11400.025*
C11−0.36763 (16)0.32850 (13)0.00028 (13)0.0173 (2)
H11−0.44120.3888−0.00020.021*
C12−0.20437 (15)0.38459 (12)0.06844 (11)0.0134 (2)
C13−0.10001 (15)0.29263 (12)0.06338 (11)0.0132 (2)
H130.01260.33140.10770.016*
C14−0.14729 (15)0.54226 (13)0.14024 (12)0.0143 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.01336 (11)0.00782 (11)0.01164 (11)0.00330 (8)−0.00119 (8)−0.00122 (8)
O10.0164 (4)0.0127 (4)0.0143 (4)0.0046 (3)−0.0009 (3)−0.0024 (3)
O20.0282 (5)0.0123 (4)0.0153 (4)0.0002 (4)0.0015 (3)0.0004 (3)
O30.0276 (5)0.0107 (4)0.0266 (5)−0.0011 (4)−0.0033 (4)−0.0028 (4)
O40.0210 (4)0.0117 (4)0.0268 (5)0.0070 (3)0.0020 (4)0.0029 (3)
O50.0177 (4)0.0099 (4)0.0155 (4)0.0030 (3)−0.0010 (3)−0.0002 (3)
O60.0356 (5)0.0144 (5)0.0177 (5)0.0072 (4)0.0029 (4)0.0006 (4)
N10.0159 (5)0.0109 (5)0.0136 (4)0.0043 (4)−0.0002 (4)0.0003 (4)
N20.0234 (5)0.0114 (5)0.0171 (5)0.0067 (4)−0.0006 (4)−0.0006 (4)
C10.0166 (5)0.0115 (5)0.0135 (5)0.0055 (4)−0.0037 (4)0.0000 (4)
C20.0169 (5)0.0110 (5)0.0134 (5)0.0044 (4)−0.0020 (4)−0.0001 (4)
C30.0197 (6)0.0153 (6)0.0171 (5)0.0041 (5)0.0020 (4)−0.0007 (4)
C40.0195 (6)0.0162 (6)0.0222 (6)0.0016 (5)0.0025 (5)0.0023 (5)
C50.0192 (6)0.0104 (5)0.0198 (6)0.0018 (4)−0.0056 (4)−0.0011 (4)
C60.0277 (6)0.0140 (6)0.0151 (5)0.0034 (5)0.0000 (5)−0.0033 (4)
C70.0245 (6)0.0133 (6)0.0144 (5)0.0014 (5)0.0019 (4)0.0000 (4)
C80.0387 (8)0.0135 (6)0.0246 (7)0.0033 (6)−0.0079 (6)−0.0060 (5)
C90.0178 (6)0.0115 (5)0.0215 (6)0.0038 (4)−0.0030 (5)−0.0017 (4)
C100.0164 (6)0.0165 (6)0.0279 (7)0.0055 (5)−0.0045 (5)−0.0003 (5)
C110.0173 (5)0.0152 (6)0.0210 (6)0.0080 (5)0.0017 (4)0.0031 (5)
C120.0168 (5)0.0112 (5)0.0125 (5)0.0045 (4)0.0031 (4)0.0024 (4)
C130.0152 (5)0.0111 (5)0.0123 (5)0.0033 (4)0.0002 (4)0.0008 (4)
C140.0185 (5)0.0114 (5)0.0134 (5)0.0048 (4)0.0053 (4)0.0024 (4)
Geometric parameters (Å, °) top
Co1—O12.0831 (8)C2—C71.3931 (16)
Co1—O1i2.0831 (8)C3—C41.3817 (17)
Co1—O52.0958 (9)C3—H30.9500
Co1—O5i2.0958 (9)C4—C51.3982 (17)
Co1—N12.1706 (10)C4—H40.9500
Co1—N1i2.1706 (10)C5—C61.3907 (18)
O1—C11.2698 (14)C6—C71.3935 (17)
O2—C11.2626 (15)C6—H60.9500
O3—C51.3603 (15)C7—H70.9500
O3—C81.4281 (17)C8—H8A0.9800
O4—C141.2381 (15)C8—H8B0.9800
O5—H510.84 (2)C8—H8C0.9800
O5—H520.81 (2)C9—C101.3865 (17)
O6—H610.81 (2)C9—H90.9500
O6—H620.84 (2)C10—C111.3866 (17)
N1—C91.3423 (15)C10—H100.9500
N1—C131.3433 (15)C11—C121.3923 (17)
N2—C141.3312 (16)C11—H110.9500
N2—H210.875 (19)C12—C131.3921 (16)
N2—H220.854 (18)C12—C141.5021 (16)
C1—C21.5000 (16)C13—H130.9500
C2—C31.3999 (17)
O1i—Co1—O1180.00 (6)C3—C4—C5120.01 (11)
O1—Co1—O589.63 (3)C3—C4—H4120.0
O1i—Co1—O590.37 (3)C5—C4—H4120.0
O1—Co1—O5i90.37 (3)O3—C5—C4115.24 (11)
O5—Co1—O5i180.00 (5)O3—C5—C6124.82 (11)
O1i—Co1—O5i89.63 (3)C6—C5—C4119.95 (11)
O1—Co1—N188.17 (3)C5—C6—C7119.43 (11)
O1i—Co1—N191.83 (3)C5—C6—H6120.3
O1—Co1—N1i91.83 (3)C7—C6—H6120.3
O1i—Co1—N1i88.17 (3)C2—C7—C6121.26 (11)
O5—Co1—N193.31 (4)C2—C7—H7119.4
O5i—Co1—N186.69 (4)C6—C7—H7119.4
O5—Co1—N1i86.69 (4)O3—C8—H8A109.5
O5i—Co1—N1i93.31 (4)O3—C8—H8B109.5
N1i—Co1—N1180.00 (4)O3—C8—H8C109.5
C1—O1—Co1130.19 (8)H8A—C8—H8B109.5
C5—O3—C8117.77 (11)H8A—C8—H8C109.5
Co1—O5—H51120.1 (13)H8B—C8—H8C109.5
Co1—O5—H52104.5 (13)N1—C9—C10123.21 (11)
H52—O5—H51109.5 (19)N1—C9—H9118.4
H62—O6—H61107 (2)C10—C9—H9118.4
C9—N1—Co1117.67 (8)C9—C10—C11118.68 (11)
C9—N1—C13117.60 (10)C9—C10—H10120.7
C13—N1—Co1124.61 (8)C11—C10—H10120.7
C14—N2—H21119.2 (12)C10—C11—C12119.02 (11)
C14—N2—H22120.4 (12)C10—C11—H11120.5
H22—N2—H21120.2 (16)C12—C11—H11120.5
O1—C1—C2116.55 (10)C11—C12—C14118.57 (10)
O2—C1—O1124.00 (11)C13—C12—C11118.26 (11)
O2—C1—C2119.43 (10)C13—C12—C14123.14 (11)
C3—C2—C1120.15 (10)N1—C13—C12123.19 (11)
C7—C2—C1121.38 (11)N1—C13—H13118.4
C7—C2—C3118.45 (11)C12—C13—H13118.4
C2—C3—H3119.6O4—C14—N2122.96 (11)
C4—C3—C2120.90 (11)O4—C14—C12118.73 (11)
C4—C3—H3119.6N2—C14—C12118.31 (10)
O5—Co1—O1—C1158.01 (10)O2—C1—C2—C3176.09 (11)
O5i—Co1—O1—C1−21.99 (10)O2—C1—C2—C7−5.62 (17)
N1—Co1—O1—C164.69 (10)C1—C2—C3—C4179.13 (11)
N1i—Co1—O1—C1−115.31 (10)C7—C2—C3—C40.78 (18)
O1—Co1—N1—C9−163.03 (9)C1—C2—C7—C6−178.10 (11)
O1i—Co1—N1—C916.97 (9)C3—C2—C7—C60.22 (19)
O1—Co1—N1—C1312.88 (9)C2—C3—C4—C5−0.99 (19)
O1i—Co1—N1—C13−167.12 (9)C3—C4—C5—O3−179.82 (11)
O5—Co1—N1—C9107.45 (9)C3—C4—C5—C60.19 (19)
O5i—Co1—N1—C9−72.55 (9)O3—C5—C6—C7−179.20 (12)
O5—Co1—N1—C13−76.64 (9)C4—C5—C6—C70.79 (19)
O5i—Co1—N1—C13103.36 (9)C5—C6—C7—C2−1.0 (2)
Co1—O1—C1—O231.88 (16)N1—C9—C10—C11−1.2 (2)
Co1—O1—C1—C2−146.38 (8)C9—C10—C11—C12−0.15 (19)
C8—O3—C5—C4179.22 (11)C10—C11—C12—C131.50 (17)
C8—O3—C5—C6−0.80 (19)C10—C11—C12—C14179.68 (11)
Co1—N1—C9—C10177.21 (10)C11—C12—C13—N1−1.72 (17)
C13—N1—C9—C101.01 (18)C14—C12—C13—N1−179.81 (10)
Co1—N1—C13—C12−175.45 (8)C11—C12—C14—O4−12.03 (16)
C9—N1—C13—C120.47 (17)C11—C12—C14—N2168.54 (11)
O1—C1—C2—C3−5.57 (16)C13—C12—C14—O4166.05 (11)
O1—C1—C2—C7172.73 (11)C13—C12—C14—N2−13.38 (17)
Symmetry codes: (i) −x, −y, −z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N2—H21···O6ii0.876 (19)1.969 (19)2.8343 (15)169.6 (17)
O5—H51···O4iii0.841 (19)1.868 (19)2.6976 (13)168.6 (19)
O5—H52···O2iv0.817 (19)1.924 (19)2.7064 (13)159.8 (19)
O6—H61···O20.81 (3)2.10 (3)2.9009 (14)170 (2)
O6—H62···O2v0.84 (2)1.97 (2)2.8068 (14)173.9 (19)
C4—H4···O4vi0.952.593.4225 (16)146
C9—H9···O1iv0.952.403.0325 (16)124
C10—H10···O5vii0.952.403.2925 (17)156
Symmetry codes: (ii) x, y+1, z; (iii) −x, −y+1, −z; (iv) −x, −y, −z; (v) −x, −y, −z+1; (vi) x+1, y, z; (vii) x−1, y, z.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N2—H21···O6i0.876 (19)1.969 (19)2.8343 (15)169.6 (17)
O5—H51···O4ii0.841 (19)1.868 (19)2.6976 (13)168.6 (19)
O5—H52···O2iii0.817 (19)1.924 (19)2.7064 (13)159.8 (19)
O6—H61···O20.81 (3)2.10 (3)2.9009 (14)170 (2)
O6—H62···O2iv0.84 (2)1.97 (2)2.8068 (14)173.9 (19)
C4—H4···O4v0.952.593.4225 (16)146
C9—H9···O1iii0.952.403.0325 (16)124
C10—H10···O5vi0.952.403.2925 (17)156
Symmetry codes: (i) x, y+1, z; (ii) −x, −y+1, −z; (iii) −x, −y, −z; (iv) −x, −y, −z+1; (v) x+1, y, z; (vi) x−1, y, z.
Acknowledgements top

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

references
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