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Acta Crystallogr Sect E Struct Rep Online. 2009 May 1; 65(Pt 5): m605–m606.
Published online 2009 April 30. doi:  10.1107/S1600536809015633
PMCID: PMC2977638

Diaqua­bis(4-methyl­amino­benzoato-κO)bis­(nicotinamide-κN 1)nickel(II)

Abstract

The title NiII complex, [Ni(C8H8NO2)2(C6H6N2O)2(H2O)2], is centrosymmetric with the Ni atom on an inversion center. The mol­ecule contains two 4-methyl­amino­benzoate (MAB) and two nicotinamide (NA) ligands and two coordinated 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 carboxyl­ate group and the adjacent benzene ring is 2.09 (14)°, while the pyridine and benzene rings are oriented at a dihedral angle of 66.15 (4)°. In the crystal structure, inter­molecular O—H(...)O and N—H(...)O hydrogen bonds link the mol­ecules into a three-dimensional network.

Related literature

For general background to transition metal complexes with biochemically active ligands, see: Antolini et al. (1982 [triangle]); Bigoli et al. (1972 [triangle]); Nadzhafov et al. (1981 [triangle]); Shnulin et al. (1981 [triangle]); Krishnamachari (1974 [triangle]). For related structures, see: Hökelek et al. (1995 [triangle], 1997 [triangle], 2007 [triangle], 2008 [triangle]); Hökelek & Necefoğlu (1996 [triangle], 1997 [triangle], 2007 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-0m605-scheme1.jpg

Experimental

Crystal data

  • [Ni(C8H8NO2)2(C6H6N2O)2(H2O)2]
  • M r = 639.31
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-0m605-efi1.jpg
  • a = 10.9331 (6) Å
  • b = 9.8467 (5) Å
  • c = 14.1992 (8) Å
  • β = 107.454 (1)°
  • V = 1458.23 (14) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.73 mm−1
  • T = 100 K
  • 0.47 × 0.32 × 0.31 mm

Data collection

  • Bruker Kappa APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.755, T max = 0.796
  • 13201 measured reflections
  • 3635 independent reflections
  • 2954 reflections with I > 2σ(I)
  • R int = 0.028

Refinement

  • R[F 2 > 2σ(F 2)] = 0.030
  • wR(F 2) = 0.085
  • S = 1.09
  • 3635 reflections
  • 217 parameters
  • 3 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.41 e Å−3
  • Δρmin = −0.42 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: ORTEP-3 for Windows (Farrugia, 1997 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]).

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

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809015633/xu2516sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809015633/xu2516Isup2.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 X-ray diffractometer.

supplementary crystallographic information

Comment

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 4-methylaminobenzoate (MAB), 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 MAB, 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 (Fig. 1).

The near equality of the C1—O1 [1.2746 (18) Å] and C1—O2 [1.2675 (17) 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: 1.256 (6) and 1.245 (6) Å in [Mn(DENA)2(C7H4ClO2)2(H2O)2], (II) (Hökelek et al., 2008), 1.265 (6) and 1.275 (6) Å in [Mn(C9H10NO2)2(H2O)4].2(H2O), (III) (Hökelek & Necefoğlu, 2007), 1.260 (4) and 1.252 (4) Å in [Zn(DENA)2(C7H4FO2)2(H2O)2],(IV) (Hökelek et al., 2007), 1.259 (9) and 1.273 (9) Å in Cu2(DENA)2(C6H5COO)4, (V) (Hökelek et al., 1995), 1.279 (4) and 1.246 (4) Å in [Zn2(DENA)2(C7H5O3)4].2H2O, (VI) (Hökelek & Necefoğlu, 1996), 1.251 (6) and 1.254 (7) Å in [Co(DENA)2(C7H5O3)2(H2O)2], (VII) (Hökelek & Necefoğlu, 1997) and 1.278 (3) and 1.246 (3) Å in [Cu(DENA)2(C7H4NO4)2(H2O)2], (VIII) (Hökelek et al., 1997). In (I), the average Ni—O bond length is 2.0581 (10) Å and the Ni atom is displaced out of the least-squares plane of the carboxylate group (O1/C1/O2) by -0.395 (1) Å. The dihedral angle between the planar carboxylate group and the benzene ring A (C2—C7) is 2.09 (14)°, while that between rings A and B (N1/C8—C12) is 66.15 (4)°.

In the crystal structure, intermolecular O—H···O and N—H···O hydrogen bonds (Table 1) link the molecules into a three-dimensional network, in which they may be effective in the stabilization of the structure.

Experimental

The title compound was prepared by the reaction of NiSO4.6(H2O) (1.31 g, 5 mmol) in H2O (30 ml) and NA (1.22 g, 10 mmol) in H2O (20 ml) with sodium 4-methylaminobenzoate (1.51 g, 10 mmol) in H2O (50 ml). The mixture was filtered and set aside to crystallize at ambient temperature for one week, giving blue single crystals.

Refinement

H atoms of water molecule, NH and NH2 groups were located in difference Fourier maps and refined isotropically, with restrains of O4—H41 = 0.878 (14) and O4 H42 = 0.897 (16) Å and H41—O4—H42 = 105.4 (18)°. The remaining H atoms were positioned geometrically with C—H = 0.93 and 0.96 Å, for aromatic and methyl H atoms, respectively, 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.

Figures

Fig. 1.
The molecular 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, 1-y, -z).

Crystal data

[Ni(C8H8NO2)2(C6H6N2O)2(H2O)2]F(000) = 668
Mr = 639.31Dx = 1.456 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 6218 reflections
a = 10.9331 (6) Åθ = 2.6–28.4°
b = 9.8467 (5) ŵ = 0.73 mm1
c = 14.1992 (8) ÅT = 100 K
β = 107.454 (1)°Block, blue
V = 1458.23 (14) Å30.47 × 0.32 × 0.31 mm
Z = 2

Data collection

Bruker Kappa APEXII CCD area-detector diffractometer3635 independent reflections
Radiation source: fine-focus sealed tube2954 reflections with I > 2σ(I)
graphiteRint = 0.028
[var phi] and ω scansθmax = 28.4°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2005)h = −14→13
Tmin = 0.755, Tmax = 0.796k = −12→13
13201 measured reflectionsl = −18→18

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)] = 0.030Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.085H atoms treated by a mixture of independent and constrained refinement
S = 1.09w = 1/[σ2(Fo2) + (0.0457P)2 + 0.1097P] where P = (Fo2 + 2Fc2)/3
3635 reflections(Δ/σ)max < 0.001
217 parametersΔρmax = 0.41 e Å3
3 restraintsΔρmin = −0.42 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
Ni10.00000.50000.00000.02520 (9)
O1−0.05431 (9)0.42926 (11)0.11617 (7)0.0298 (2)
O2−0.20986 (10)0.28374 (11)0.03794 (7)0.0331 (3)
O3−0.24476 (12)0.91313 (14)−0.21749 (8)0.0441 (3)
O40.18759 (10)0.52817 (12)0.08904 (8)0.0295 (2)
H410.209 (2)0.547 (2)0.1523 (11)0.055 (6)*
H420.212 (2)0.600 (2)0.0608 (16)0.087 (9)*
N1−0.05647 (11)0.69514 (13)0.02746 (8)0.0269 (3)
N2−0.23426 (13)1.10935 (16)−0.13262 (11)0.0354 (3)
H21−0.217 (2)1.156 (2)−0.0742 (16)0.062 (6)*
H22−0.2690 (18)1.1511 (18)−0.1881 (14)0.039 (5)*
N3−0.12888 (14)0.12206 (18)0.48807 (10)0.0422 (4)
H31−0.190 (2)0.071 (2)0.4877 (16)0.061 (7)*
C1−0.13324 (13)0.33378 (16)0.11561 (10)0.0290 (3)
C2−0.13399 (13)0.28004 (16)0.21324 (10)0.0291 (3)
C3−0.21846 (14)0.17675 (17)0.22136 (11)0.0305 (3)
H3−0.27730.14280.16460.037*
C4−0.21573 (14)0.12488 (17)0.31176 (11)0.0328 (3)
H4−0.27230.05590.31520.039*
C5−0.12885 (14)0.17437 (18)0.39904 (11)0.0335 (4)
C6−0.04453 (14)0.27794 (18)0.39144 (11)0.0368 (4)
H60.01450.31210.44810.044*
C7−0.04892 (14)0.32956 (18)0.29965 (11)0.0334 (3)
H70.00670.39940.29590.040*
C8−0.04561 (13)0.74589 (17)0.11720 (10)0.0288 (3)
H8−0.00690.69300.17230.035*
C9−0.08955 (14)0.87357 (17)0.13112 (11)0.0321 (3)
H9−0.08140.90520.19440.039*
C10−0.14588 (14)0.95401 (18)0.04957 (11)0.0315 (3)
H10−0.17491.04090.05710.038*
C11−0.15803 (13)0.90173 (16)−0.04382 (10)0.0287 (3)
C12−0.11315 (13)0.77289 (17)−0.05083 (10)0.0285 (3)
H12−0.12270.7378−0.11340.034*
C13−0.21654 (14)0.97680 (18)−0.13847 (11)0.0333 (4)
C14−0.04606 (17)0.1690 (2)0.58153 (12)0.0495 (5)
H14A−0.06420.11950.63400.074*
H14B−0.06050.26410.58880.074*
H14C0.04170.15470.58410.074*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Ni10.01580 (14)0.04990 (18)0.01093 (13)−0.00137 (10)0.00555 (10)−0.00041 (10)
O10.0223 (5)0.0548 (7)0.0150 (5)−0.0029 (4)0.0097 (4)−0.0004 (4)
O20.0224 (5)0.0601 (7)0.0174 (5)−0.0052 (5)0.0070 (4)0.0009 (5)
O30.0456 (7)0.0668 (8)0.0148 (5)0.0090 (6)0.0013 (5)0.0035 (5)
O40.0196 (5)0.0539 (7)0.0139 (5)−0.0019 (4)0.0037 (4)−0.0018 (4)
N10.0163 (5)0.0507 (7)0.0146 (6)−0.0017 (5)0.0061 (5)0.0002 (5)
N20.0270 (7)0.0584 (9)0.0188 (7)0.0069 (6)0.0037 (6)0.0069 (6)
N30.0257 (7)0.0787 (11)0.0224 (7)−0.0043 (7)0.0074 (6)0.0137 (7)
C10.0172 (7)0.0540 (9)0.0179 (7)0.0031 (6)0.0086 (6)0.0016 (6)
C20.0168 (6)0.0542 (9)0.0185 (7)0.0036 (6)0.0087 (5)0.0045 (6)
C30.0181 (7)0.0548 (9)0.0204 (7)0.0017 (6)0.0084 (6)−0.0003 (6)
C40.0203 (7)0.0547 (10)0.0267 (8)0.0006 (6)0.0119 (6)0.0055 (7)
C50.0190 (7)0.0630 (10)0.0206 (7)0.0058 (6)0.0092 (6)0.0100 (7)
C60.0200 (7)0.0717 (11)0.0175 (7)−0.0031 (7)0.0035 (6)0.0058 (7)
C70.0193 (7)0.0609 (10)0.0211 (7)−0.0022 (6)0.0078 (6)0.0058 (7)
C80.0196 (7)0.0541 (9)0.0130 (6)0.0013 (6)0.0052 (5)0.0034 (6)
C90.0268 (7)0.0552 (9)0.0146 (7)0.0030 (7)0.0066 (6)−0.0005 (6)
C100.0226 (7)0.0537 (9)0.0188 (7)0.0038 (6)0.0072 (6)0.0012 (6)
C110.0151 (6)0.0558 (9)0.0148 (7)0.0000 (6)0.0038 (5)0.0027 (6)
C120.0172 (6)0.0556 (9)0.0128 (6)−0.0017 (6)0.0046 (5)−0.0002 (6)
C130.0191 (7)0.0634 (11)0.0162 (7)0.0035 (6)0.0037 (6)0.0047 (6)
C140.0309 (9)0.0953 (15)0.0205 (8)−0.0025 (9)0.0053 (7)0.0164 (9)

Geometric parameters (Å, °)

Ni1—O12.0362 (9)C3—C41.373 (2)
Ni1—O1i2.0362 (9)C3—H30.9300
Ni1—O42.0800 (11)C4—H40.9300
Ni1—O4i2.0800 (11)C5—N31.3652 (19)
Ni1—N12.0903 (13)C5—C41.403 (2)
Ni1—N1i2.0903 (13)C5—C61.400 (2)
O1—C11.2746 (18)C6—C71.386 (2)
O2—C11.2675 (17)C6—H60.9300
O3—C131.2407 (19)C7—H70.9300
O4—H410.878 (14)C8—C91.381 (2)
O4—H420.897 (16)C8—H80.9300
N1—C81.3404 (17)C9—C101.386 (2)
N1—C121.3389 (18)C9—H90.9300
N2—C131.326 (2)C10—H100.9300
N2—H210.92 (2)C11—C101.391 (2)
N2—H220.869 (19)C11—C121.375 (2)
N3—C141.440 (2)C11—C131.499 (2)
N3—H310.83 (2)C12—H120.9300
C2—C11.4861 (19)C14—H14A0.9600
C2—C71.387 (2)C14—H14B0.9600
C3—C21.402 (2)C14—H14C0.9600
O1i—Ni1—O1180.0C3—C4—C5121.02 (15)
O1—Ni1—O491.56 (4)C3—C4—H4119.5
O1i—Ni1—O488.44 (4)C5—C4—H4119.5
O1i—Ni1—O4i91.56 (4)N3—C5—C4119.91 (15)
O1—Ni1—O4i88.44 (4)N3—C5—C6121.94 (15)
O1—Ni1—N189.38 (4)C6—C5—C4118.14 (13)
O1i—Ni1—N190.62 (4)C5—C6—H6120.0
O1—Ni1—N1i90.62 (4)C7—C6—C5120.10 (14)
O1i—Ni1—N1i89.38 (4)C7—C6—H6120.0
O4—Ni1—O4i180.00 (7)C2—C7—H7119.1
O4—Ni1—N193.24 (4)C6—C7—C2121.85 (15)
O4i—Ni1—N186.76 (4)C6—C7—H7119.1
O4—Ni1—N1i86.76 (4)N1—C8—C9122.69 (13)
O4i—Ni1—N1i93.24 (4)N1—C8—H8118.7
N1i—Ni1—N1180.00 (6)C9—C8—H8118.7
C1—O1—Ni1127.49 (9)C8—C9—C10119.16 (14)
Ni1—O4—H41123.9 (14)C8—C9—H9120.4
Ni1—O4—H42102.0 (16)C10—C9—H9120.4
H41—O4—H42105.4 (18)C9—C10—C11118.46 (15)
C8—N1—Ni1124.97 (10)C9—C10—H10120.8
C12—N1—Ni1117.37 (9)C11—C10—H10120.8
C12—N1—C8117.58 (13)C10—C11—C13124.42 (15)
C13—N2—H21123.9 (13)C12—C11—C10118.45 (13)
C13—N2—H22116.2 (12)C12—C11—C13117.12 (13)
H21—N2—H22119.8 (18)N1—C12—C11123.64 (13)
C5—N3—C14123.89 (16)N1—C12—H12118.2
C5—N3—H31116.4 (15)C11—C12—H12118.2
C14—N3—H31118.7 (15)O3—C13—N2123.55 (15)
O1—C1—C2116.74 (13)O3—C13—C11119.03 (15)
O2—C1—O1124.17 (13)N2—C13—C11117.41 (14)
O2—C1—C2119.08 (13)N3—C14—H14A109.5
C3—C2—C1121.55 (13)N3—C14—H14B109.5
C7—C2—C1120.67 (13)N3—C14—H14C109.5
C7—C2—C3117.77 (13)H14A—C14—H14B109.5
C2—C3—H3119.4H14A—C14—H14C109.5
C4—C3—C2121.11 (14)H14B—C14—H14C109.5
C4—C3—H3119.4
O4—Ni1—O1—C1−142.35 (12)C1—C2—C7—C6−177.70 (14)
O4i—Ni1—O1—C137.65 (12)C3—C2—C7—C61.3 (2)
N1i—Ni1—O1—C1−55.58 (12)C4—C3—C2—C1177.98 (14)
N1—Ni1—O1—C1124.42 (12)C4—C3—C2—C7−1.0 (2)
O1i—Ni1—N1—C8−145.11 (11)C2—C3—C4—C50.5 (2)
O1—Ni1—N1—C834.89 (11)C4—C5—N3—C14−178.12 (16)
O1i—Ni1—N1—C1238.14 (10)C6—C5—N3—C141.4 (3)
O1—Ni1—N1—C12−141.86 (10)N3—C5—C4—C3179.35 (15)
O4—Ni1—N1—C8−56.63 (11)N3—C5—C6—C7−179.07 (16)
O4i—Ni1—N1—C8123.37 (11)C4—C5—C6—C70.5 (2)
O4—Ni1—N1—C12126.62 (10)C6—C5—C4—C3−0.2 (2)
O4i—Ni1—N1—C12−53.38 (10)C5—C6—C7—C2−1.1 (3)
Ni1—O1—C1—O2−14.1 (2)N1—C8—C9—C10−0.8 (2)
Ni1—O1—C1—C2166.19 (9)C8—C9—C10—C111.1 (2)
Ni1—N1—C8—C9−177.10 (11)C12—C11—C10—C9−0.2 (2)
C12—N1—C8—C9−0.4 (2)C13—C11—C10—C9−179.89 (14)
Ni1—N1—C12—C11178.29 (11)C10—C11—C12—N1−1.0 (2)
C8—N1—C12—C111.3 (2)C13—C11—C12—N1178.68 (13)
C3—C2—C1—O1178.85 (13)C10—C11—C13—O3−166.51 (15)
C3—C2—C1—O2−0.8 (2)C10—C11—C13—N214.0 (2)
C7—C2—C1—O1−2.2 (2)C12—C11—C13—O313.8 (2)
C7—C2—C1—O2178.09 (14)C12—C11—C13—N2−165.61 (13)

Symmetry codes: (i) −x, −y+1, −z.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N2—H21···O2ii0.92 (2)2.01 (2)2.9150 (18)167.9 (18)
N3—H31···O4iii0.84 (2)2.44 (2)3.162 (2)144.6 (19)
O4—H41···O3iv0.88 (2)1.81 (2)2.6849 (16)179 (2)
O4—H42···O2i0.89 (2)1.80 (2)2.6464 (15)156 (2)

Symmetry codes: (ii) x, y+1, z; (iii) x−1/2, −y+1/2, z+1/2; (iv) x+1/2, −y+3/2, z+1/2; (i) −x, −y+1, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: XU2516).

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