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Acta Cryst. (2009). E65, m466-m467    [ doi:10.1107/S1600536809011209 ]

Diaquabis(2-chlorobenzoato-[kappa]O)bis(nicotinamide-[kappa]N1)nickel(II)

T. Hökelek, H. Dal, B. Tercan, F. E. Özbek and H. Necefoglu

Abstract top

The title NiII complex, [Ni(C7H4ClO2)2(C6H6N2O)2(H2O)2], is centrosymmetric with the Ni atom located on an inversion centre. The molecule contains two 2-chlorobenzoate (CB) and two nicotinamide (NA) ligands and two water molecules, all ligands being monodentate. The four O atoms in the equatorial plane around the Ni atom form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination is completed by the two N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxyl group and the adjacent benzene ring is 29.48 (16)°, while the pyridine and benzene rings are oriented at a dihedral angle of 83.16 (5)°. In the crystal structure, O-H...O and N-H...O hydrogen bonds link the molecules into infinite chains. [pi]-[pi] Contacts between the benzene and pyridine rings [centroid-centroid distance = 3.952 (1) Å] may further stabilize the crystal structure. There is also a C-H...[pi] interaction.

Comment top

Transition metal complexes with biochemically active ligands frequently show interesting physical and/or chemical properties, as a result they may find applications in biological systems (Antolini et al., 1982). The structural functions and coordination relationships of the arylcarboxylate ion in transition metal complexes of benzoic acid derivatives change depending on the nature and position of the substituent groups on the benzene ring, the nature of the additional ligand molecule or solvent, and the medium of the synthesis (Nadzhafov et al., 1981; Shnulin et al., 1981). Nicotinamide (NA) is one form of niacin and a deficiency of this vitamin leads to loss of copper from the body, known as pellagra disease. Victims of pellagra show unusually high serum and urinary copper levels (Krishnamachari, 1974). On the other hand, the nicotinic acid derivative N,N-diethylnicotinamide (DENA) is an important respiratory stimulant (Bigoli et al., 1972).

The structure determination of the title compound, (I), a nickel complex with two 2-chlorobenzoate (CB), two nicotinamide (NA) ligands and two water molecules, was undertaken in order to determine the properties of the ligands and also to compare the results obtained with those reported previously.

Compound (I) is a monomeric complex, with the Ni atom on a centre of symmetry. It contains two CB, two NA ligands and two water molecules (Fig. 1). All ligands are monodentate. The four O atoms (O1, O4, and the symmetry-related atoms, O1', O4') in the equatorial plane around the Ni atom 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 (Table 1 and Fig. 1). The intramolecular O—H···O hydrogen bonds (Table 2) link two of the water molecules to the two CB ligands (Fig. 1).

The near equality of the C1—O1 [1.267 (3) Å] and C1—O2 [1.258 (3) Å] bonds in the carboxylate group indicates a delocalized bonding arrangement, rather than localized single and double bonds, and may be compared with the corresponding distances: 1.262 (3) and 1.249 (3) Å in [Mn(DENA)2(C8H5O3)2(H2O)2], (II) (Sertçelik et al., 2009a), 1.263 (4) and 1.249 (4) Å in [Ni(DENA)2(C8H5O3)2(H2O)2], (III) (Sertçelik et al., 2009b), 1.262 (5) and 1.257 (5) Å in [Co(DENA)2(C8H5O3)2(H2O)2], (IV) (Sertçelik et al., 2009c), 1.244 (4) and 1.270 (4) Å in [Co(NA)2(H2O)4](C7H4FO2)2, (V) (Özbek et al., 2009), 1.284 (2), 1.248 (2) and 1.278 (2), 1.241 (2) Å in [Zn(NA)2(C8H8NO2)2], (VI) (Tercan et al., 2009), 1.256 (6) and 1.245 (6) Å in [Mn(DENA)2(C7H4ClO2)2(H2O)2], (VII) (Hökelek et al., 2008), 1.265 (6) and 1.275 (6) Å in [Mn(C9H10NO2)2(H2O)4].2(H2O), (VIII) (Hökelek & Necefoğlu, 2007), 1.260 (4) and 1.252 (4) Å in [Zn(DENA)2(C7H4FO2)2(H2O)2], (IX) (Hökelek et al., 2007), 1.259 (9) and 1.273 (9) Å in Cu2(DENA)2(C6H5COO)4, (X) (Hökelek et al., 1995), 1.279 (4) and 1.246 (4) Å in [Zn2(DENA)2(C7H5O3)4].2H2O, (XI) (Hökelek & Necefouglu, 1996), 1.251 (6) and 1.254 (7) Å in [Co(DENA)2(C7H5O3)2(H2O)2], (XII) (Hökelek & Necefouglu, 1997) and 1.278 (3) and 1.246 (3) Å in [Cu(DENA)2(C7H4NO4)2(H2O)2], (XIII) (Hökelek et al., 1997). In (I), the average Ni—O bond length is 2.1269 (16) Å and the Ni atom is displaced out of the least-squares plane of the carboxylate group (O1/C1/O2) by 0.661 (1) Å. The dihedral angle between the planar carboxylate group and the benzene ring A (C2—C7) is 29.48 (16)°, while that between rings A and B (N1/C8—C12) is 83.16 (5)°.

In the crystal structure, intermolecular O—H···O and N—H···O hydrogen bonds (Table 2) link the molecules into infinite chains (Fig. 2), in which they may be effective in the stabilization of the structure. The π-π contacts between the 2-chlorobenzoate rings and the pyridine rings of NA ligands, Cg2—Cg1i [symmetry code: (i) x - 1/2, 1/2 - y, 1/2 + z, where Cg1 and Cg2 are centroids of the rings A (C2—C7) and B (N1/C9—C13), respectively] may further stabilize the structure, with centroid-centroid distance of 3.952 (1) Å. There is also a C—H···π interaction (Table 2).

Related literature top

For general backgroud, see: Antolini et al. (1982); Bigoli et al. (1972); Krishnamachari (1974); Nadzhafov et al. (1981); Shnulin et al. (1981). For related structures, see: Hökelek & Necefouglu (1996, 1997); Hökelek & Necefoğlu (2007); Hökelek et al. (1995, 1997, 2007, 2008); Özbek et al. (2009); Sertçelik et al. (2009a,b,c); Tercan et al. (2009).

Experimental top

The title compound was prepared by the reaction of Ni(SO4).6(H2O) (1.31 g, 5 mmol) in H2O (20 ml) and NA (1.22 g, 10 mmol) in H2O (20 ml) with sodium 2-chlorobenzoate (1.785 g, 10 mmol) in H2O (50 ml). The mixture was filtered and set aside to crystallize at ambient temperature for 5 d, giving orange single crystals.

Refinement top

H atoms of water molecule and NH2 group were located in difference Fourier maps and refined isotropically, with restrain of O4—H42 = 0.850 (18) Å. The remaining H atoms were positioned geometrically with C—H = 0.93 Å, for aromatic H atoms and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C).

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: Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen bonds are shown as dashed lines. Primed atoms are generated by the symmetry operator (1 - x, -y, -z).
[Figure 2] Fig. 2. A partial packing diagram of (I) viewed down the a axis, showing hydrogen bonds (dotted lines) linking the molecules into chains, where b and c axes are horizontal and vertical, respectively. H atoms not involved in hydrogen bonding are omitted.
Diaquabis(2-chlorobenzoato-κO)bis(nicotinamide-κN1)nickel(II) top
Crystal data top
[Ni(C7H4ClO2)2(C6H6N2O)2(H2O)2]F(000) = 668
Mr = 650.10Dx = 1.622 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 5500 reflections
a = 7.8602 (3) Åθ = 2.4–28.3°
b = 17.9529 (6) ŵ = 0.99 mm−1
c = 9.8446 (3) ÅT = 100 K
β = 106.600 (2)°Block, orange
V = 1331.31 (8) Å30.45 × 0.30 × 0.25 mm
Z = 2
Data collection top
Bruker Kappa-APEXII CCD area-detector
diffractometer		3301 independent reflections
Radiation source: fine-focus sealed tube2626 reflections with I > 2σ(I)
graphiteRint = 0.064
φ and ω scansθmax = 28.3°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		h = −10→7
Tmin = 0.710, Tmax = 0.784k = −23→21
11754 measured reflectionsl = −11→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)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.107H atoms treated by a mixture of independent and constrained refinement
S = 1.07 w = 1/[σ2(Fo2) + (0.0492P)2 + 1.0761P]
where P = (Fo2 + 2Fc2)/3
3301 reflections(Δ/σ)max < 0.001
202 parametersΔρmax = 0.77 e Å−3
1 restraintΔρmin = −0.69 e Å−3
Crystal data top
[Ni(C7H4ClO2)2(C6H6N2O)2(H2O)2]V = 1331.31 (8) Å3
Mr = 650.10Z = 2
Monoclinic, P21/nMo Kα radiation
a = 7.8602 (3) ŵ = 0.99 mm−1
b = 17.9529 (6) ÅT = 100 K
c = 9.8446 (3) Å0.45 × 0.30 × 0.25 mm
β = 106.600 (2)°
Data collection top
Bruker Kappa-APEXII CCD area-detector
diffractometer		3301 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		2626 reflections with I > 2σ(I)
Tmin = 0.710, Tmax = 0.784Rint = 0.064
11754 measured reflectionsθmax = 28.3°
Refinement top
R[F2 > 2σ(F2)] = 0.040H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.107Δρmax = 0.77 e Å−3
S = 1.07Δρmin = −0.69 e Å−3
3301 reflectionsAbsolute structure: ?
202 parametersFlack parameter: ?
1 restraintRogers parameter: ?
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
Ni10.50000.00000.00000.01322 (13)
Cl10.40816 (8)0.28820 (3)−0.32584 (6)0.02186 (16)
O10.6153 (2)0.09893 (9)−0.04613 (15)0.0135 (3)
O20.3868 (2)0.13652 (10)−0.22542 (16)0.0155 (4)
O30.0484 (2)0.00967 (10)0.32471 (17)0.0183 (4)
O40.2363 (2)0.04330 (10)−0.08886 (17)0.0146 (4)
H410.261 (4)0.0763 (19)−0.141 (3)0.030 (9)*
H420.153 (3)0.0172 (16)−0.141 (3)0.029*
N10.4964 (3)0.04416 (10)0.19906 (19)0.0115 (4)
N20.1426 (3)0.08165 (13)0.5195 (2)0.0188 (5)
H210.221 (4)0.1030 (18)0.573 (3)0.026 (9)*
H220.060 (4)0.0657 (17)0.550 (3)0.023 (8)*
C10.5480 (3)0.13795 (13)−0.1555 (2)0.0121 (4)
C20.6718 (3)0.18573 (13)−0.2104 (2)0.0124 (5)
C30.8477 (3)0.16293 (13)−0.1863 (2)0.0143 (5)
H30.88870.1224−0.12710.017*
C40.9630 (3)0.19869 (14)−0.2478 (2)0.0164 (5)
H41.07970.1824−0.22940.020*
C50.9033 (3)0.25927 (14)−0.3375 (2)0.0166 (5)
H50.97890.2823−0.38200.020*
C60.7319 (3)0.28498 (14)−0.3601 (2)0.0154 (5)
H60.69260.3262−0.41790.019*
C70.6181 (3)0.24896 (13)−0.2959 (2)0.0129 (5)
C80.6344 (3)0.08184 (13)0.2847 (2)0.0132 (5)
H80.73790.08680.25770.016*
C90.6273 (3)0.11327 (14)0.4113 (2)0.0169 (5)
H90.72400.13930.46780.020*
C100.4743 (3)0.10541 (13)0.4526 (2)0.0152 (5)
H100.46680.12620.53720.018*
C110.3318 (3)0.06602 (13)0.3664 (2)0.0123 (4)
C120.3496 (3)0.03681 (13)0.2405 (2)0.0125 (5)
H120.25430.01080.18190.015*
C130.1630 (3)0.05107 (13)0.4022 (2)0.0142 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ni10.0129 (2)0.0162 (2)0.00877 (19)−0.00046 (17)0.00017 (15)−0.00017 (15)
Cl10.0173 (3)0.0200 (3)0.0261 (3)0.0068 (2)0.0027 (2)0.0055 (2)
O10.0147 (8)0.0153 (8)0.0076 (7)−0.0023 (6)−0.0017 (6)0.0006 (6)
O20.0117 (8)0.0213 (9)0.0109 (7)−0.0014 (7)−0.0013 (6)0.0023 (6)
O30.0149 (9)0.0267 (10)0.0116 (7)−0.0053 (7)0.0013 (6)−0.0039 (7)
O40.0134 (9)0.0176 (9)0.0103 (7)−0.0009 (7)−0.0006 (6)0.0013 (6)
N10.0115 (9)0.0122 (10)0.0090 (8)0.0000 (7)−0.0002 (7)0.0004 (7)
N20.0157 (11)0.0294 (13)0.0116 (9)−0.0060 (9)0.0043 (8)−0.0067 (9)
C10.0148 (11)0.0124 (11)0.0082 (9)−0.0007 (9)0.0018 (8)−0.0030 (8)
C20.0154 (11)0.0129 (11)0.0072 (9)−0.0011 (9)0.0004 (8)−0.0023 (8)
C30.0147 (11)0.0137 (11)0.0112 (10)−0.0007 (9)−0.0016 (8)−0.0014 (8)
C40.0133 (11)0.0187 (12)0.0157 (11)−0.0020 (9)0.0016 (9)−0.0026 (9)
C50.0190 (12)0.0174 (12)0.0127 (10)−0.0053 (10)0.0035 (9)−0.0016 (9)
C60.0189 (12)0.0145 (12)0.0099 (10)−0.0022 (9)−0.0007 (8)0.0008 (8)
C70.0126 (11)0.0140 (11)0.0092 (10)0.0017 (9)−0.0013 (8)−0.0020 (8)
C80.0120 (11)0.0154 (12)0.0109 (10)−0.0009 (9)0.0010 (8)0.0006 (8)
C90.0155 (12)0.0196 (13)0.0125 (10)−0.0047 (10)−0.0012 (9)−0.0033 (9)
C100.0177 (12)0.0188 (12)0.0071 (9)−0.0023 (9)0.0005 (8)−0.0028 (8)
C110.0134 (11)0.0134 (11)0.0082 (9)−0.0007 (9)−0.0001 (8)0.0007 (8)
C120.0131 (11)0.0123 (11)0.0091 (9)−0.0006 (9)−0.0018 (8)0.0011 (8)
C130.0132 (11)0.0180 (12)0.0097 (9)0.0004 (9)0.0008 (8)0.0017 (8)
Geometric parameters (Å, °) top
Ni1—O1i2.1017 (16)C3—H30.9300
Ni1—O12.1017 (16)C4—C31.383 (3)
Ni1—O42.1520 (16)C4—C51.395 (3)
Ni1—O4i2.1520 (16)C4—H40.9300
Ni1—N1i2.1217 (18)C5—C61.381 (3)
Ni1—N12.1217 (18)C5—H50.9300
Cl1—C71.740 (2)C6—H60.9300
O1—C11.267 (3)C7—C21.404 (3)
O2—C11.258 (3)C7—C61.393 (3)
O3—C131.246 (3)C8—C91.384 (3)
O4—H410.85 (3)C8—H80.9300
O4—H420.850 (18)C9—H90.9300
N1—C81.350 (3)C10—C91.382 (3)
N1—C121.335 (3)C10—H100.9300
N2—C131.329 (3)C11—C101.390 (3)
N2—H210.79 (3)C11—C121.389 (3)
N2—H220.84 (3)C11—C131.492 (3)
C1—C21.508 (3)C12—H120.9300
C2—C31.396 (3)
O1i—Ni1—O1180.00 (5)C4—C3—C2122.0 (2)
O1i—Ni1—O488.18 (6)C4—C3—H3119.0
O1—Ni1—O491.82 (6)C3—C4—C5119.7 (2)
O1i—Ni1—O4i91.82 (6)C3—C4—H4120.2
O1—Ni1—O4i88.18 (6)C5—C4—H4120.2
O4—Ni1—O4i180.00 (9)C4—C5—H5120.1
O1i—Ni1—N1i90.24 (7)C6—C5—C4119.9 (2)
O1—Ni1—N1i89.76 (7)C6—C5—H5120.1
O1i—Ni1—N189.76 (7)C5—C6—C7119.7 (2)
O1—Ni1—N190.24 (7)C5—C6—H6120.2
N1i—Ni1—N1180.00 (14)C7—C6—H6120.2
N1i—Ni1—O491.44 (7)C2—C7—Cl1122.46 (19)
N1—Ni1—O488.56 (7)C6—C7—Cl1115.85 (18)
N1i—Ni1—O4i88.56 (7)C6—C7—C2121.7 (2)
N1—Ni1—O4i91.44 (7)N1—C8—C9122.3 (2)
Ni1—O4—H4198 (2)N1—C8—H8118.8
Ni1—O4—H42122 (2)C9—C8—H8118.8
H41—O4—H42107 (3)C8—C9—H9120.5
C1—O1—Ni1123.37 (14)C10—C9—C8119.1 (2)
C8—N1—Ni1122.93 (16)C10—C9—H9120.5
C12—N1—Ni1119.06 (14)C9—C10—C11119.3 (2)
C12—N1—C8117.97 (19)C9—C10—H10120.4
C13—N2—H21121 (2)C11—C10—H10120.4
C13—N2—H22118 (2)C10—C11—C13124.3 (2)
H22—N2—H21118 (3)C12—C11—C10117.9 (2)
O1—C1—C2117.6 (2)C12—C11—C13117.80 (19)
O2—C1—O1124.4 (2)N1—C12—C11123.4 (2)
O2—C1—C2117.89 (19)N1—C12—H12118.3
C3—C2—C1118.8 (2)C11—C12—H12118.3
C3—C2—C7116.9 (2)O3—C13—N2122.2 (2)
C7—C2—C1124.1 (2)O3—C13—C11119.9 (2)
C2—C3—H3119.0N2—C13—C11117.9 (2)
O4—Ni1—O1—C1−35.17 (18)C1—C2—C3—C4172.0 (2)
O4i—Ni1—O1—C1144.83 (18)C7—C2—C3—C4−2.5 (3)
N1i—Ni1—O1—C156.26 (18)C5—C4—C3—C2−0.3 (3)
N1—Ni1—O1—C1−123.74 (18)C3—C4—C5—C62.5 (3)
O1i—Ni1—N1—C8136.61 (18)C4—C5—C6—C7−1.7 (3)
O1—Ni1—N1—C8−43.39 (18)Cl1—C7—C2—C110.4 (3)
O1i—Ni1—N1—C12−45.66 (17)Cl1—C7—C2—C3−175.42 (16)
O1—Ni1—N1—C12134.34 (17)C6—C7—C2—C1−170.8 (2)
O4—Ni1—N1—C1242.53 (17)C6—C7—C2—C33.4 (3)
O4i—Ni1—N1—C12−137.47 (17)Cl1—C7—C6—C5177.53 (17)
O4—Ni1—N1—C8−135.20 (18)C2—C7—C6—C5−1.3 (3)
O4i—Ni1—N1—C844.80 (18)N1—C8—C9—C100.6 (4)
Ni1—O1—C1—O222.1 (3)C11—C10—C9—C80.2 (4)
Ni1—O1—C1—C2−154.02 (15)C12—C11—C10—C9−0.7 (3)
Ni1—N1—C8—C9176.99 (17)C13—C11—C10—C9177.3 (2)
C12—N1—C8—C9−0.8 (3)C10—C11—C12—N10.5 (3)
Ni1—N1—C12—C11−177.65 (17)C13—C11—C12—N1−177.6 (2)
C8—N1—C12—C110.2 (3)C10—C11—C13—O3−173.6 (2)
O1—C1—C2—C328.5 (3)C10—C11—C13—N24.8 (4)
O1—C1—C2—C7−157.4 (2)C12—C11—C13—O34.4 (3)
O2—C1—C2—C3−147.9 (2)C12—C11—C13—N2−177.1 (2)
O2—C1—C2—C726.2 (3)
Symmetry codes: (i) −x+1, −y, −z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O4—H41···O20.84 (4)1.82 (3)2.630 (2)161 (3)
O4—H42···O3ii0.85 (3)2.09 (3)2.887 (2)156 (3)
N2—H21···O2iii0.79 (3)2.13 (3)2.865 (3)156 (3)
N2—H22···O3iv0.84 (3)2.16 (3)2.934 (3)153 (3)
C9—H9···Cg1iii0.932.883.596 (2)135
Symmetry codes: (ii) −x, −y, −z; (iii) x, y, z+1; (iv) −x, −y, −z+1.
Table 1
Selected geometric parameters (Å, °) top
Ni1—O12.1017 (16)Ni1—N12.1217 (18)
Ni1—O42.1520 (16)
O1i—Ni1—O488.18 (6)O1—Ni1—N190.24 (7)
O1—Ni1—O491.82 (6)N1i—Ni1—O491.44 (7)
O1i—Ni1—N189.76 (7)N1—Ni1—O488.56 (7)
Symmetry codes: (i) −x+1, −y, −z.
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O4—H41···O20.84 (4)1.82 (3)2.630 (2)161 (3)
O4—H42···O3ii0.85 (3)2.09 (3)2.887 (2)156 (3)
N2—H21···O2iii0.79 (3)2.13 (3)2.865 (3)156 (3)
N2—H22···O3iv0.84 (3)2.16 (3)2.934 (3)153 (3)
C9—H9···Cg1iii0.932.883.596 (2)135
Symmetry codes: (ii) −x, −y, −z; (iii) x, y, z+1; (iv) −x, −y, −z+1.
Acknowledgements top

The authors are indebted to Anadolu University and Medicinal Plants and Medicine Research Centre of Anadolu University, Eskişehir, Turkey, for the use of the X-ray diffractometer.

references
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