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Acta Cryst. (2010). E66, m394-m395    [ doi:10.1107/S1600536810008834 ]

Diaquabis(5-bromo-2-hydroxybenzoato)bis(N-methylnicotinamide)zinc(II)

Z. Bujdosová, J. Kuchár and K. Györyová

Abstract top

The title mononuclear complex molecule, [Zn(C7H4BrO3)2(C7H8N2O)2(H2O)2], has a crystallographically imposed centre of symmetry. The zinc(II) atom is coordinated by two N atoms from two N-methylnicotinamide ligands, two O atoms from two 5-bromosalicylate anions and two aqua O atoms in a slightly distorted octahedral geometry. Intramolecular O-H...O hydrogen-bonding interactions are present. In the crystal structure, molecules are linked by intermolecular O-H...O and N-H...O hydrogen bonds, forming a two-dimensional network perpendicular to [100].

Comment top

The complexes of carboxylic acids with metals, e.g. zinc, are interesting due to different coordination modes of a carboxylate group bound to a metal ion. It is well documented that heterocyclic compounds, especially N-donor ligand systems, play a significant role in many biological systems, being a component of several vitamins and drugs (Nagar, 1990; Cavagiolio et al., 2000). As a part of our ongoing studies of zinc(II) carboxylates (Györyová et al., 2005; Györyová et al., 2006; Bujdošová et al., 2009) we have been exploring the synthesis and crystal structure of zinc(II) 5-bromosalicylate containing N-methylnicotinamide, shown at in vitro study to be a potent anti-inflammatory agent (Gebicki et al., 2003).

In the title monomeric complex [Zn(C7H4BrO3)2(C7H8N2O)2(H2O)2] (Fig. 1), the zinc(II) atom, which lies on an inversion centre, exhibits a slightly distorted octahedral coordination geometry. The coordination sphere consists of three pairs of trans-arranged monodentate ligands. The two N-methylnicotinamide ligands are coordinated to the zinc atom through nitrogen atoms of the pyridine rings. The 5-bromosalicylate anion is coordinated through one oxygen atom of the carboxylate group. The similar distances O1—C1 (1.256 (2) Å) and O2—C1 (1.262 (2) Å) in the carboxylate group indicate a delocalized bonding arrangement and may be compared with the corresponding distances found in [Zn(C7H4ClO2)2(C10H14N2O)2(H2O)2] (Sarı et al., 2007). The plane of the carboxylate group is approximately coplanar with the plane of the benzene ring; the dihedral angle between these planes is 5.5 (3)°. Such behaviour is not unusual; a similar arrangement was observed in other compounds (e.g. diaquabis(N,N-diethylnicotinamide-N)bis(4-fluorobenzoato-O)zinc(II) (Hökelek et al., 2007)). All other geometric parameters of the coordinated anion are similar to that found in free 5-bromosalicylic acid (Liu et al., 2004). The distorted octahedral coordination is completed by two pyridine nitrogen atoms of two N-methylnicotinamide ligands in the axial positions. The Zn—N distance (2.1583 (9) Å) is in good agreement with the values reported for other octahedrally coordinated zinc(II) complexes [viz., Diaquabis(4-chlorobenzoato)bis(N,N-diethylnicotinamide)zinc(II), Zn—N: 2.157 (3) Å; Sarı et al., 2007]. The coordination environment of the zinc(II) atom is completed by water molecules, forming with carboxylate oxygen atoms the basal plane of the distorted octahedron. The Zn—O distance (2.1396 (8) Å) is comparable with those found in similar compounds [viz. diaquabis(2-bromobenzoato)bis(N,N-diethylnicotinamide)zinc(II), Zn—O: 2.1269 (12) Å; Hökelek et al., 2009b]. Intramolecular hydrogen bonding interactions involving the hydroxyl groups and carboxylate oxygen atoms (O3—H1O3···O2) and the equatorially coordinated water molecule and carboxylate oxygen atom (O5—H2O5···O2) stabilize the molecular structure (Fig. 2). Intramolecular hydrogen bonds also influences the orientation and delocalized character of carboxylate group. The molecules of the title compound are linked into a two-dimensional network perpendicular to [100] by intermolecular O5—H1O5···O4 and N2—H1N2···O3 hydrogen bonds (Fig. 3).

Related literature top

For general background to the properties of carboxylic acid–metal complexes, see: Nagar (1990); Cavagiolio et al. (2000). For the synthesis and properties of zinc(II) carboxylates reported by our group, see: Györyová et al. (2005, 2006); Bujdošová et al. (2009); Gebicki et al. (2003). For related structures, see: Necefoglu et al. (2001a,b); Hökelek et al. (2007, 2009a,b); Öztürk et al. (2008); Sarı et al. (2007); Liu et al. (2004).

Experimental top

Analytical reagent grade chemicals were used for the preparation of the title compound. The synthesis was carried out by reaction of aqueous solutions (20 ml) of ZnCl2 (0.14 g, 1 mmol) and NaHCO3 (0.17 g, 2 mmol). After complete removal of chloride anions, an acetone solution (10 ml) of 5-bromosalicylic acid (0.44 g, 2 mmol) was added. The resulting solution of (5-BrC6H3-2-(OH)COO)2Zn (0.50 g, 1 mmol) was mixed with an aqueous solution (10 ml) of N-methylnicotinamide (0.27 g, 2 mmol). The reaction mixture was stirred for 2 h and left aside for crystallization at room temperature. After two days, a small amount of colourless bright crystals appeared. The resulting crystals were isolated by filtration.

Refinement top

The hydrogen atoms of the water molecule were located in difference Fourier map and refined with the O—H distances constrained to 0.82 Å and with Uiso(H) = 1.5Ueq(O). The H atom bound to N2 was located in a difference Fourier map and refined Uiso(H) = 1.2Ueq(N). All other H atoms were positioned geometrically and constrained to ride on their parent atoms, with O—H = 0.82 Å, C—H = 0.93–0.96 Å, and with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(C, O) for methyl and hydroxyl H atoms.

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Crystal Impact, 2007); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Symmetry code: (i) 1-x, -y, -z.
[Figure 2] Fig. 2. View of the intramolecular hydrogen bonds (dashed lines) of the title compound. Hydrogen atoms of aromatic rings and methyl groups are omitted for clarity.
[Figure 3] Fig. 3. View of the intermolecular hydrogen bonds (dashed lines) of the title compound. Hydrogen atoms of aromatic rings and methyl groups are omitted for clarity. Symmetry codes: (i) x, -1+y, z; (ii) x, y, 1+z
Diaquabis(5-bromo-2-hydroxybenzoato)bis(N-methylnicotinamide)zinc(II) top
Crystal data top
[Zn(C7H4BrO3)2(C7H8N2O)2(H2O)2]Z = 1
Mr = 805.73F(000) = 404
Triclinic, P1Dx = 1.760 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.1600 (2) ÅCell parameters from 19248 reflections
b = 10.1122 (3) Åθ = 3.0–29.6°
c = 10.4291 (3) ŵ = 3.50 mm−1
α = 66.800 (3)°T = 290 K
β = 74.334 (2)°Prism, colourless
γ = 80.743 (2)°0.56 × 0.30 × 0.26 mm
V = 760.15 (4) Å3
Data collection top
Oxford Diffraction Xcalibur Sapphire2
diffractometer		3153 independent reflections
Radiation source: Enhance (Mo) X-ray Source2686 reflections with I > 2σ(I)
graphiteRint = 0.024
Detector resolution: 8.3438 pixels mm-1θmax = 26.5°, θmin = 3.0°
ω scansh = −10→10
Absorption correction: numerical
[Clark & Reid (1995) in CrysAlis PRO (Oxford Diffraction, 2009)]		k = −12→12
Tmin = 0.289, Tmax = 0.484l = −13→13
32240 measured reflections
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)] = 0.022Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.064H-atom parameters constrained
S = 1.15 w = 1/[σ2(Fo2) + (0.0404P)2]
where P = (Fo2 + 2Fc2)/3
3153 reflections(Δ/σ)max < 0.001
195 parametersΔρmax = 0.50 e Å−3
0 restraintsΔρmin = −0.49 e Å−3
Crystal data top
[Zn(C7H4BrO3)2(C7H8N2O)2(H2O)2]γ = 80.743 (2)°
Mr = 805.73V = 760.15 (4) Å3
Triclinic, P1Z = 1
a = 8.1600 (2) ÅMo Kα radiation
b = 10.1122 (3) ŵ = 3.50 mm−1
c = 10.4291 (3) ÅT = 290 K
α = 66.800 (3)°0.56 × 0.30 × 0.26 mm
β = 74.334 (2)°
Data collection top
Oxford Diffraction Xcalibur Sapphire2
diffractometer		3153 independent reflections
Absorption correction: numerical
[Clark & Reid (1995) in CrysAlis PRO (Oxford Diffraction, 2009)]		2686 reflections with I > 2σ(I)
Tmin = 0.289, Tmax = 0.484Rint = 0.024
32240 measured reflectionsθmax = 26.5°
Refinement top
R[F2 > 2σ(F2)] = 0.022H-atom parameters constrained
wR(F2) = 0.064Δρmax = 0.50 e Å−3
S = 1.15Δρmin = −0.49 e Å−3
3153 reflectionsAbsolute structure: ?
195 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 > 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
Zn10.50000.00000.00000.02312 (9)
O10.67676 (14)−0.02707 (13)−0.17587 (12)0.0305 (3)
O20.5864 (2)0.14251 (15)−0.36177 (15)0.0493 (4)
O30.6562 (2)0.11216 (16)−0.60156 (15)0.0550 (4)
H1O30.60750.1466−0.54090.083*
C10.6699 (2)0.02704 (19)−0.30545 (19)0.0299 (4)
C20.7659 (2)−0.05359 (18)−0.40050 (18)0.0270 (4)
C30.7497 (2)−0.00760 (19)−0.54230 (19)0.0348 (4)
C40.8343 (3)−0.0873 (2)−0.6265 (2)0.0425 (5)
H40.8233−0.0574−0.72040.051*
C50.9340 (3)−0.2099 (2)−0.5713 (2)0.0403 (5)
H50.9899−0.2629−0.62760.048*
C60.9505 (2)−0.25379 (19)−0.43114 (19)0.0319 (4)
C70.8667 (2)−0.17721 (18)−0.34631 (18)0.0295 (4)
H70.8777−0.2085−0.25220.035*
Br11.08861 (3)−0.42202 (2)−0.35493 (2)0.05222 (9)
N10.66055 (11)0.14385 (9)0.01039 (9)0.0245 (3)
N20.48397 (11)0.41145 (9)0.24800 (9)0.0384 (4)
H1N20.45600.32370.28760.046*
C80.82847 (11)0.13682 (9)−0.04349 (9)0.0302 (4)
H80.87410.0682−0.08430.036*
C90.9368 (2)0.2262 (2)−0.0414 (2)0.0373 (4)
H91.05330.2178−0.07940.045*
C100.8694 (2)0.32926 (19)0.0186 (2)0.0352 (4)
H100.93990.39190.02050.042*
C110.6960 (2)0.33753 (16)0.07550 (17)0.0250 (3)
C120.5966 (2)0.24263 (16)0.06900 (17)0.0241 (3)
H120.47990.24790.10720.029*
C130.6211 (2)0.44766 (17)0.14122 (19)0.0282 (4)
C140.39754 (10)0.50534 (8)0.32554 (9)0.0531 (6)
H14C0.28900.46920.38280.080*
H14A0.38090.60110.25830.080*
H14B0.46600.50740.38640.080*
O40.68500 (13)0.56491 (9)0.09551 (11)0.0373 (3)
O50.63493 (12)−0.17592 (8)0.13428 (10)0.0300 (3)
H2O50.5760−0.18340.21380.045*
H1O50.6509−0.25310.12290.045*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Zn10.02369 (15)0.02253 (14)0.02842 (16)−0.00151 (10)−0.00284 (11)−0.01690 (11)
O10.0301 (6)0.0377 (7)0.0285 (7)−0.0004 (5)−0.0009 (5)−0.0214 (6)
O20.0659 (10)0.0349 (7)0.0386 (8)0.0174 (7)−0.0051 (7)−0.0168 (6)
O30.0737 (11)0.0479 (9)0.0376 (9)0.0209 (8)−0.0187 (8)−0.0152 (7)
C10.0294 (9)0.0296 (9)0.0322 (10)−0.0047 (7)0.0013 (7)−0.0175 (8)
C20.0290 (9)0.0285 (9)0.0242 (9)−0.0033 (7)0.0008 (7)−0.0143 (7)
C30.0416 (11)0.0330 (10)0.0272 (9)−0.0004 (8)−0.0060 (8)−0.0102 (8)
C40.0580 (13)0.0465 (12)0.0239 (10)0.0003 (10)−0.0069 (9)−0.0170 (9)
C50.0489 (12)0.0433 (11)0.0322 (10)−0.0008 (9)0.0002 (9)−0.0246 (9)
C60.0315 (10)0.0310 (9)0.0344 (10)0.0009 (7)−0.0031 (8)−0.0172 (8)
C70.0321 (9)0.0342 (9)0.0247 (9)−0.0028 (7)−0.0033 (7)−0.0152 (7)
Br10.05614 (16)0.04580 (14)0.05557 (16)0.01938 (10)−0.01506 (11)−0.02663 (11)
N10.0260 (7)0.0214 (7)0.0303 (8)−0.0008 (5)−0.0066 (6)−0.0140 (6)
N20.0486 (10)0.0283 (8)0.0416 (10)−0.0049 (7)−0.0014 (8)−0.0213 (7)
C80.0287 (9)0.0277 (9)0.0376 (10)0.0011 (7)−0.0036 (7)−0.0192 (8)
C90.0248 (9)0.0371 (10)0.0539 (12)−0.0040 (8)−0.0013 (8)−0.0249 (9)
C100.0346 (10)0.0300 (9)0.0462 (11)−0.0087 (7)−0.0085 (8)−0.0173 (8)
C110.0327 (9)0.0181 (8)0.0272 (9)−0.0012 (6)−0.0100 (7)−0.0097 (7)
C120.0262 (8)0.0215 (8)0.0273 (9)0.0006 (6)−0.0069 (7)−0.0122 (7)
C130.0331 (9)0.0229 (8)0.0359 (10)0.0034 (7)−0.0163 (7)−0.0151 (7)
C140.0612 (15)0.0488 (13)0.0547 (14)−0.0050 (11)0.0057 (11)−0.0365 (11)
O40.0450 (8)0.0217 (6)0.0504 (8)−0.0032 (5)−0.0097 (6)−0.0191 (6)
O50.0316 (7)0.0239 (6)0.0381 (7)0.0014 (5)−0.0059 (5)−0.0175 (5)
Geometric parameters (Å, °) top
Zn1—O1i2.0879 (11)N1—C81.3352 (13)
Zn1—O12.0879 (11)N1—C121.3359 (17)
Zn1—O52.1396 (9)N2—C131.328 (2)
Zn1—O5i2.1396 (9)N2—C141.4609 (13)
Zn1—N1i2.1583 (9)N2—H1N20.8578
Zn1—N12.1583 (9)C8—C91.372 (2)
O1—C11.256 (2)C8—H80.9300
O2—C11.262 (2)C9—C101.387 (2)
O3—C31.341 (2)C9—H90.9300
O3—H1O30.8200C10—C111.382 (2)
C1—C21.508 (2)C10—H100.9300
C2—C71.386 (2)C11—C121.384 (2)
C2—C31.402 (3)C11—C131.497 (2)
C3—C41.396 (2)C12—H120.9300
C4—C51.377 (3)C13—O41.235 (2)
C4—H40.9300C14—H14C0.9600
C5—C61.389 (3)C14—H14A0.9600
C5—H50.9300C14—H14B0.9600
C6—C71.376 (2)O5—H2O50.8196
C6—Br11.8968 (18)O5—H1O50.8197
C7—H70.9300
O1i—Zn1—O1180.00 (8)C6—C7—H7119.9
O1i—Zn1—O592.30 (4)C2—C7—H7119.9
O1—Zn1—O587.70 (4)C8—N1—C12117.96 (11)
O1i—Zn1—O5i87.70 (4)C8—N1—Zn1120.28 (7)
O1—Zn1—O5i92.30 (4)C12—N1—Zn1121.77 (9)
O5—Zn1—O5i180.00 (10)C13—N2—C14122.98 (11)
O1i—Zn1—N1i91.23 (4)C13—N2—H1N2120.1
O1—Zn1—N1i88.77 (4)C14—N2—H1N2115.5
O5—Zn1—N1i91.78 (3)N1—C8—C9122.98 (11)
O5i—Zn1—N1i88.22 (3)N1—C8—H8118.5
O1i—Zn1—N188.77 (4)C9—C8—H8118.5
O1—Zn1—N191.23 (4)C8—C9—C10118.76 (15)
O5—Zn1—N188.22 (4)C8—C9—H9120.6
O5i—Zn1—N191.78 (3)C10—C9—H9120.6
N1i—Zn1—N1180.00 (4)C11—C10—C9118.99 (16)
C1—O1—Zn1128.42 (11)C11—C10—H10120.5
C3—O3—H1O3109.5C9—C10—H10120.5
O1—C1—O2125.03 (16)C10—C11—C12118.22 (15)
O1—C1—C2117.54 (15)C10—C11—C13119.77 (15)
O2—C1—C2117.42 (16)C12—C11—C13122.01 (15)
C7—C2—C3119.42 (15)N1—C12—C11123.07 (14)
C7—C2—C1119.96 (15)N1—C12—H12118.5
C3—C2—C1120.57 (16)C11—C12—H12118.5
O3—C3—C4118.17 (17)O4—C13—N2123.41 (16)
O3—C3—C2122.26 (16)O4—C13—C11120.51 (15)
C4—C3—C2119.57 (17)N2—C13—C11116.08 (15)
C5—C4—C3120.41 (18)N2—C14—H14C109.5
C5—C4—H4119.8N2—C14—H14A109.5
C3—C4—H4119.8H14C—C14—H14A109.5
C4—C5—C6119.57 (17)N2—C14—H14B109.5
C4—C5—H5120.2H14C—C14—H14B109.5
C6—C5—H5120.2H14A—C14—H14B109.5
C7—C6—C5120.74 (17)Zn1—O5—H2O5100.9
C7—C6—Br1119.51 (14)Zn1—O5—H1O5119.2
C5—C6—Br1119.74 (14)H2O5—O5—H1O5111.8
C6—C7—C2120.28 (16)
O5—Zn1—O1—C1167.76 (16)O1—Zn1—N1—C8−24.26 (8)
O5i—Zn1—O1—C1−12.24 (16)O5—Zn1—N1—C863.39 (8)
N1i—Zn1—O1—C175.93 (14)O5i—Zn1—N1—C8−116.61 (8)
N1—Zn1—O1—C1−104.07 (14)O1i—Zn1—N1—C12−24.81 (11)
Zn1—O1—C1—O224.7 (3)O1—Zn1—N1—C12155.19 (11)
Zn1—O1—C1—C2−153.98 (11)O5—Zn1—N1—C12−117.16 (10)
O1—C1—C2—C7−4.4 (2)O5i—Zn1—N1—C1262.84 (10)
O2—C1—C2—C7176.77 (16)C12—N1—C8—C9−0.15 (17)
O1—C1—C2—C3173.34 (16)Zn1—N1—C8—C9179.32 (11)
O2—C1—C2—C3−5.5 (3)N1—C8—C9—C10−0.4 (2)
C7—C2—C3—O3−178.98 (17)C8—C9—C10—C110.7 (3)
C1—C2—C3—O33.3 (3)C9—C10—C11—C12−0.5 (3)
C7—C2—C3—C40.4 (3)C9—C10—C11—C13179.74 (17)
C1—C2—C3—C4−177.40 (16)C8—N1—C12—C110.3 (2)
O3—C3—C4—C5179.01 (19)Zn1—N1—C12—C11−179.13 (12)
C2—C3—C4—C5−0.4 (3)C10—C11—C12—N10.0 (2)
C3—C4—C5—C6−0.2 (3)C13—C11—C12—N1179.73 (14)
C4—C5—C6—C70.8 (3)C14—N2—C13—O4−2.0 (2)
C4—C5—C6—Br1−179.66 (15)C14—N2—C13—C11178.73 (11)
C5—C6—C7—C2−0.8 (3)C10—C11—C13—O431.6 (2)
Br1—C6—C7—C2179.66 (13)C12—C11—C13—O4−148.18 (17)
C3—C2—C7—C60.2 (3)C10—C11—C13—N2−149.10 (16)
C1—C2—C7—C6178.00 (16)C12—C11—C13—N231.1 (2)
O1i—Zn1—N1—C8155.74 (8)
Symmetry codes: (i) −x+1, −y, −z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O3—H1O3···O20.821.812.540 (2)147
N2—H1N2···O3ii0.862.553.1109 (19)123
O5—H2O5···O2i0.821.882.6694 (18)162
O5—H1O5···O4iii0.821.942.7568 (13)179
Symmetry codes: (ii) x, y, z+1; (i) −x+1, −y, −z; (iii) x, y−1, z.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O3—H1O3···O20.821.812.540 (2)147
N2—H1N2···O3i0.862.553.1109 (19)123
O5—H2O5···O2ii0.821.882.6694 (18)162
O5—H1O5···O4iii0.821.942.7568 (13)179
Symmetry codes: (i) x, y, z+1; (ii) −x+1, −y, −z; (iii) x, y−1, z.
Acknowledgements top

Financial support by the Slovak Ministry of Education (VEGA project No. 1/0122/08) is gratefully acknowledged.

references
References top

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