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Acta Cryst. (2007). E63, m1873-m1874    [ doi:10.1107/S1600536807028358 ]

Diaquabis(4-bromobenzoato-[kappa]O)bis(nicotinamide-[kappa]N1)cobalt(II)

T. Hökelek, N. Çaylak and H. Necefoglu

Abstract top

The title complex, [Co(C7H4BrO2)2(C6H6N2O)2(H2O)2], is monomeric and centrosymmetric, and contains two water molecules, two 4-bromobenzoate (BB) anions and two nicotinamide (NA) ligands, all acting as monodentate ligands. The four nearest O atoms in the equatorial plane around the Co atom form a slightly distorted square-planar arrangement, while the distorted octahedral coordination is completed by the two NA N atoms in the axial positions. Intermolecular O-H...O and N-H...O hydrogen bonds link the molecules into two-dimensional sheets.

Comment top

Transition metal complexes with biochemical molecules show interesting physical and/or chemical properties, in which they may find applications in biological systems (Antolini et al., 1982). The structure-function-coordination relationships of the arylcarboxylate ion in CoII complexes of benzoic acid derivatives change depending on the nature and position of the substituted groups in the phenyl ring, the nature of the additional ligand molecule or solvent, and the medium of synthesis (Nadzhafov et al., 1981; Shnulin et al., 1981; Antsyshkina et al., 1980; Amiraslanov et al., 1979; Adiwidjaja et al., 1978). To the best of our knowledge, only a few structures of CoII complexes with nicotinic and/or benzoic acid derivatives as ligands have been reported to date (Amiraslanov et al., 1979; Nadzhafov et al., 1981; Mikelashvili, 1982; Hökelek & Necefoğlu, 1997; 1998; 1999a,b,c; 2007a; Çaylak, Hökelek & Necefoğlu, 2007; Çaylak, Hökelek et al., 2007).

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

The title monomeric complex, (I), with the Co atom on a centre of symmetry contains two BB and two NA ligands and two water molecules denoted by primed and unprimed labels, respectively, in Fig. 1. A l l ligands are monodentate. The four symmetry-related carboxylate and water O atoms (O1, O4, and the symmetry related atoms, O1', O4') 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 N atoms of the NA ligands (N1, and the symmetry related atom, N1') in the axial positions (Table 1 and Fig. 1), as in the similar compounds (Hökelek & Necefoğlu, 1997; 1998; 1999a,b,c; 2007a; Çaylak, Hökelek & Necefoğlu, 2007; Çaylak, Hökelek et al., 2007).

The near equality of the C1—O1 [1.256 (5) Å] and C1—O2 [1.254 (5) Å] bonds in the carboxylate group indicates a delocalized bonding arrangement, rather than localized single and double bonds, as in bis(4-hydroxybenzoato-κO)bis(nicotinamide-κN)zinc(II) (Necefoğlu et al., 2002), diaquabis[4-(dimethylamino)benzoato-κO]-(nicotinamide-κN1)cobalt(II) dihydrate (Hökelek & Necefoğlu, 2007a), tetraaquabis[4-(dimethylamino)benzoato-κO]manganese(II) dihydrate (Hökelek & Necefoğlu, 2007b), diaquabis[4-(dimethylamino)benzoato-κO]-(nicotinamide-κN1)manganese(II) dihydrate (Hökelek & Necefoğlu, 2007c), diaquabis(4-fluorobenzoato-κO)bis(nicotinamide-κN1)cobalt(II) (Çaylak, Hökelek & Necefoğlu, 2007) and diaquabis(4-chlorobenzoato-κO)bis(nicotinamide-κN)cobalt(II) (Çaylak, Hökelek et al., 2007). This may influenced by the intra- and intermolecular O—H···O and N—H···O hydrogen bonds involving the carboxylate O atoms (Table 2). The Co atom is displaced out of the least-squares plane of the carboxylate group (O1/C1/O2) by −0.465 (1) Å. The dihedral angle between the planar carboxyl group and the benzene ring A (C2—C7) is 23.2 (3)°, while that between rings A and B (N1/C8—C12) is A/B = 88.82 (11)°.

As can be seen from the packing diagram (Fig. 2), intermolecular O—H···O and N—H···O hydrogen bonds (Table 2), firstly link the amide groups of NA molecules to form centrosymmetric hydrogen bonded dimers, they further link the molecules into two-dimensional sheets lying parallel to the ab plane.

Related literature top

For general background, see: Antolini et al. (1982); Nadzhafov et al. (1981); Shnulin et al. (1981); Antsyshkina et al. (1980); Amiraslanov et al. (1979); Adiwidjaja et al. (1978); Mikelashvili (1982). For related structures, see: Hökelek & Necefoğlu (1997, 1998, 1999a,b,c, 2007a,b,c); Çaylak, Hökelek & Necefoğlu (2007); Çaylak, Hökelek et al. (2007).

For related literature, see: Necefoğlu et al. (2002).

Experimental top

The title compound, (I), was prepared by the reaction of CoSO4 (1.55 g, 10 mmol) and NA (2.44 g, 20 mmol) in H2O (100 ml) with sodium 4-bromobenzoate (4.46 g, 20 mmol) in H2O (100 ml). The mixture was filtered and set aside to crystallize at ambient temperature for several days, giving pink single crystals.

Refinement top

H atoms of water molecule and NH2 group were located in a difference Fourier map and refined isotropically [O—H = 0.91 (2) and 0.95 (5) Å and Uiso(H) = 0.055 (15) and 0.072 (17) Å2; N—H = 0.87 (2) and 0.87 (4) Å and Uiso(H) = 0.046 (14) and 0.076 (18) Å2]. 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: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); 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 (−x, −y, −z).
[Figure 2] Fig. 2. A partial packing diagram of the title compound, showing hydrogen bonds (dashed lines) linking the complexes into two-dimensional sheets in the ab planes. H atoms not involved in hydrogen bonding are omitted.
Diaquabis(4-bromobenzoato-κO)bis(nicotinamide-κN1)cobalt(II) top
Crystal data top
[Co(C7H4BrO2)2(C6H6N2O)2(H2O)2]Z = 1
Mr = 739.22F000 = 369
Triclinic, P1Dx = 1.723 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 7.6202 (1) ÅCell parameters from 25 reflections
b = 9.9593 (3) Åθ = 3.6–22.2º
c = 10.1125 (2) ŵ = 3.46 mm−1
α = 77.92 (1)ºT = 294 (2) K
β = 85.65 (1)ºPrism, pink
γ = 71.65 (2)º0.30 × 0.20 × 0.15 mm
V = 712.25 (9) Å3
Data collection top
Enraf–Nonius TurboCAD-4
diffractometer		Rint = 0.022
Radiation source: fine-focus sealed tubeθmax = 26.3º
Monochromator: graphiteθmin = 3.0º
T = 294(2) Kh = −9→9
non–profiled ω scansk = −12→12
Absorption correction: ψ scan
(North et al., 1968)		l = −12→0
Tmin = 0.446, Tmax = 0.5953 standard reflections
3067 measured reflections every 120 min
2895 independent reflections intensity decay: 1%
1968 reflections with I > 2σ(I)
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.042H atoms treated by a mixture of
independent and constrained refinement
wR(F2) = 0.110  w = 1/[σ2(Fo2) + (0.0519P)2 + 0.47P]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max < 0.001
2895 reflectionsΔρmax = 0.93 e Å−3
203 parametersΔρmin = −0.58 e Å−3
8 restraintsExtinction correction: none
Primary atom site location: structure-invariant direct methods
Crystal data top
[Co(C7H4BrO2)2(C6H6N2O)2(H2O)2]γ = 71.65 (2)º
Mr = 739.22V = 712.25 (9) Å3
Triclinic, P1Z = 1
a = 7.6202 (1) ÅMo Kα
b = 9.9593 (3) ŵ = 3.46 mm−1
c = 10.1125 (2) ÅT = 294 (2) K
α = 77.92 (1)º0.30 × 0.20 × 0.15 mm
β = 85.65 (1)º
Data collection top
Enraf–Nonius TurboCAD-4
diffractometer		1968 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)		Rint = 0.022
Tmin = 0.446, Tmax = 0.5953 standard reflections
3067 measured reflections every 120 min
2895 independent reflections intensity decay: 1%
Refinement top
R[F2 > 2σ(F2)] = 0.0428 restraints
wR(F2) = 0.110H atoms treated by a mixture of
independent and constrained refinement
S = 1.02Δρmax = 0.93 e Å−3
2895 reflectionsΔρmin = −0.58 e Å−3
203 parameters
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
Co0.00000.00000.50000.0266 (2)
Br0.51245 (9)0.28767 (7)1.09652 (7)0.0754 (3)
O10.1170 (4)0.0145 (3)0.6725 (3)0.0351 (7)
O2−0.1297 (4)0.1515 (4)0.7667 (3)0.0456 (8)
O30.4344 (4)0.3394 (3)0.4903 (4)0.0480 (8)
O40.2740 (4)−0.0730 (3)0.4218 (3)0.0366 (7)
H410.241 (7)−0.107 (5)0.349 (4)0.072 (17)*
H420.357 (5)−0.150 (4)0.473 (4)0.055 (15)*
N1−0.0003 (4)0.2151 (3)0.4081 (3)0.0306 (7)
N20.3329 (6)0.5588 (4)0.3608 (5)0.0491 (10)
H210.261 (5)0.628 (4)0.304 (4)0.046 (14)*
H220.423 (5)0.579 (5)0.391 (5)0.076 (18)*
C10.0411 (5)0.0925 (4)0.7565 (4)0.0298 (9)
C20.1624 (5)0.1255 (4)0.8464 (4)0.0283 (8)
C30.3438 (6)0.1150 (4)0.8117 (4)0.0348 (9)
H30.39590.07590.73670.042*
C40.4502 (6)0.1617 (5)0.8863 (4)0.0408 (10)
H40.57190.15580.86130.049*
C50.3718 (6)0.2168 (5)0.9980 (4)0.0390 (10)
C60.1944 (7)0.2219 (6)1.0394 (5)0.0497 (12)
H60.14560.25481.11800.060*
C70.0898 (6)0.1773 (5)0.9623 (4)0.0425 (11)
H7−0.03130.18210.98850.051*
C80.1419 (5)0.2577 (4)0.4292 (4)0.0308 (9)
H80.23830.19260.48250.037*
C90.1538 (5)0.3957 (4)0.3753 (4)0.0308 (9)
C100.0106 (6)0.4892 (4)0.2960 (5)0.0416 (11)
H100.01280.58210.25780.050*
C11−0.1365 (6)0.4450 (5)0.2729 (5)0.0451 (11)
H11−0.23370.50710.21850.054*
C12−0.1373 (5)0.3087 (4)0.3312 (4)0.0352 (9)
H12−0.23780.27990.31650.042*
C130.3196 (6)0.4291 (5)0.4132 (5)0.0376 (10)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co0.0225 (4)0.0273 (4)0.0340 (4)−0.0106 (3)−0.0033 (3)−0.0088 (3)
Br0.0728 (4)0.0981 (5)0.0812 (5)−0.0396 (4)−0.0130 (3)−0.0487 (4)
O10.0310 (15)0.0391 (16)0.0392 (16)−0.0102 (13)−0.0060 (12)−0.0151 (13)
O20.0283 (16)0.062 (2)0.0497 (19)−0.0106 (14)−0.0019 (14)−0.0227 (16)
O30.0409 (17)0.0350 (17)0.072 (2)−0.0151 (14)−0.0194 (16)−0.0062 (16)
O40.0265 (15)0.0399 (17)0.0454 (18)−0.0111 (13)−0.0009 (13)−0.0107 (14)
N10.0282 (17)0.0294 (18)0.0370 (19)−0.0124 (14)−0.0038 (14)−0.0060 (15)
N20.053 (3)0.035 (2)0.067 (3)−0.026 (2)−0.015 (2)−0.003 (2)
C10.031 (2)0.029 (2)0.031 (2)−0.0111 (17)−0.0032 (17)−0.0030 (17)
C20.0273 (19)0.028 (2)0.029 (2)−0.0059 (16)−0.0043 (16)−0.0065 (17)
C30.033 (2)0.040 (2)0.034 (2)−0.0122 (18)0.0012 (17)−0.0122 (19)
C40.033 (2)0.051 (3)0.042 (3)−0.015 (2)−0.0011 (19)−0.014 (2)
C50.038 (2)0.043 (3)0.041 (2)−0.014 (2)−0.0072 (19)−0.014 (2)
C60.051 (3)0.067 (3)0.039 (3)−0.017 (2)0.003 (2)−0.030 (2)
C70.034 (2)0.058 (3)0.040 (3)−0.018 (2)0.007 (2)−0.018 (2)
C80.029 (2)0.030 (2)0.036 (2)−0.0104 (17)−0.0064 (17)−0.0069 (17)
C90.034 (2)0.025 (2)0.035 (2)−0.0113 (17)0.0002 (17)−0.0086 (17)
C100.045 (2)0.025 (2)0.053 (3)−0.0119 (19)−0.005 (2)−0.001 (2)
C110.042 (3)0.035 (2)0.055 (3)−0.010 (2)−0.012 (2)0.000 (2)
C120.026 (2)0.038 (2)0.042 (2)−0.0100 (18)−0.0054 (18)−0.0073 (19)
C130.041 (2)0.033 (2)0.047 (3)−0.020 (2)0.003 (2)−0.015 (2)
Geometric parameters (Å, °) top
Co—O1i2.069 (3)C2—C71.386 (6)
Co—O12.069 (3)C3—H30.9300
Co—O42.132 (3)C4—C31.386 (6)
Co—O4i2.132 (3)C4—H40.9300
Co—N12.148 (3)C5—C41.373 (6)
Co—N1i2.148 (3)C5—C61.373 (6)
Br—C51.889 (4)C6—H60.9300
O1—C11.256 (5)C7—C61.379 (6)
O2—C11.254 (5)C7—H70.9300
O3—C131.221 (5)C8—N11.329 (5)
O4—H410.95 (5)C8—C91.397 (5)
O4—H420.91 (2)C8—H80.9300
N2—C131.323 (5)C11—C121.364 (6)
N2—H210.87 (4)C11—C101.378 (6)
N2—H220.87 (2)C11—H110.9300
C1—C21.495 (5)C12—N11.330 (5)
C2—C31.377 (6)C12—H120.9300
O1i—Co—O1180.0C2—C3—H3119.4
O1i—Co—O492.63 (11)C4—C3—H3119.4
O1—Co—O487.37 (11)C5—C4—C3118.5 (4)
O1i—Co—O4i87.37 (11)C5—C4—H4120.7
O1—Co—O4i92.63 (11)C3—C4—H4120.7
O4—Co—O4i180.0C4—C5—C6121.6 (4)
O1i—Co—N189.70 (12)C4—C5—Br118.9 (3)
O1—Co—N190.30 (12)C6—C5—Br119.5 (3)
O4—Co—N187.23 (11)C5—C6—C7118.8 (4)
O4i—Co—N192.77 (11)C5—C6—H6120.6
O1i—Co—N1i90.30 (12)C7—C6—H6120.6
O1—Co—N1i89.70 (12)C6—C7—C2121.0 (4)
O4—Co—N1i92.77 (11)C6—C7—H7119.5
O4i—Co—N1i87.23 (11)C2—C7—H7119.5
N1—Co—N1i180.0N1—C8—C9123.2 (4)
C1—O1—Co126.9 (2)N1—C8—H8118.4
Co—O4—H42118 (3)C9—C8—H8118.4
Co—O4—H4196 (3)C10—C9—C8117.2 (4)
H42—O4—H41106 (3)C10—C9—C13126.1 (4)
C8—N1—C12118.0 (3)C8—C9—C13116.7 (4)
C8—N1—Co118.8 (3)C9—C10—C11119.8 (4)
C12—N1—Co123.1 (3)C9—C10—H10120.1
C13—N2—H21129 (3)C11—C10—H10120.1
C13—N2—H22115 (3)C12—C11—C10118.9 (4)
H21—N2—H22115 (4)C12—C11—H11120.5
O2—C1—O1125.1 (4)C10—C11—H11120.5
O2—C1—C2116.7 (3)N1—C12—C11122.8 (4)
O1—C1—C2118.1 (3)N1—C12—H12118.6
C3—C2—C7118.6 (4)C11—C12—H12118.6
C3—C2—C1121.1 (4)O3—C13—N2122.6 (4)
C7—C2—C1120.1 (3)O3—C13—C9120.5 (4)
C2—C3—C4121.2 (4)N2—C13—C9116.9 (4)
O4—Co—O1—C1156.5 (3)C1—C2—C7—C6−173.5 (4)
O4i—Co—O1—C1−23.5 (3)C5—C4—C3—C21.1 (7)
N1—Co—O1—C169.3 (3)Br—C5—C4—C3−177.6 (3)
N1i—Co—O1—C1−110.7 (3)C6—C5—C4—C32.3 (7)
O1i—Co—N1—C8−141.9 (3)C4—C5—C6—C7−3.4 (7)
O1—Co—N1—C838.1 (3)Br—C5—C6—C7176.4 (4)
O4—Co—N1—C8−49.3 (3)C2—C7—C6—C51.2 (7)
O4i—Co—N1—C8130.7 (3)N1—C8—C9—C10−0.6 (6)
O1i—Co—N1—C1238.5 (3)N1—C8—C9—C13177.6 (4)
O1—Co—N1—C12−141.5 (3)C9—C8—N1—C120.3 (6)
O4—Co—N1—C12131.1 (3)C9—C8—N1—Co−179.3 (3)
O4i—Co—N1—C12−48.9 (3)C8—C9—C10—C110.1 (7)
Co—O1—C1—O216.3 (6)C13—C9—C10—C11−177.9 (4)
Co—O1—C1—C2−159.9 (3)C10—C9—C13—O3176.2 (4)
O2—C1—C2—C3−154.9 (4)C8—C9—C13—O3−1.8 (6)
O1—C1—C2—C321.6 (6)C10—C9—C13—N2−2.9 (7)
O2—C1—C2—C720.5 (6)C8—C9—C13—N2179.0 (4)
O1—C1—C2—C7−163.0 (4)C10—C11—C12—N1−1.1 (7)
C7—C2—C3—C4−3.2 (6)C12—C11—C10—C90.7 (7)
C1—C2—C3—C4172.3 (4)C11—C12—N1—C80.5 (6)
C3—C2—C7—C62.0 (7)C11—C12—N1—Co−179.9 (3)
Symmetry codes: (i) −x, −y, −z+1.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O4—H41···O20.95 (4)1.70 (5)2.635 (4)166 (5)
O4—H42···O3ii0.91 (4)2.03 (4)2.893 (4)156 (4)
N2—H21···O2iii0.87 (4)2.10 (4)2.884 (6)151 (3)
N2—H22···O3iv0.87 (4)2.11 (5)2.935 (6)160 (4)
Symmetry codes: (ii) −x+1, −y, −z+1; (iii) −x, −y+1, −z+1; (iv) −x+1, −y+1, −z+1.
Table 1
Selected geometric parameters (Å, °) top
Co—O12.069 (3)O1—C11.256 (5)
Co—O42.132 (3)O2—C11.254 (5)
Co—N12.148 (3)
O1i—Co—O492.63 (11)O1—Co—N190.30 (12)
O1—Co—O487.37 (11)O4—Co—N187.23 (11)
O1i—Co—N189.70 (12)O4i—Co—N192.77 (11)
Symmetry codes: (i) −x, −y, −z+1.
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O4—H41···O20.95 (4)1.70 (5)2.635 (4)166 (5)
O4—H42···O3ii0.91 (4)2.03 (4)2.893 (4)156 (4)
N2—H21···O2iii0.87 (4)2.10 (4)2.884 (6)151 (3)
N2—H22···O3iv0.87 (4)2.11 (5)2.935 (6)160 (4)
Symmetry codes: (ii) −x+1, −y, −z+1; (iii) −x, −y+1, −z+1; (iv) −x+1, −y+1, −z+1.
Acknowledgements top

The authors acknowledge the purchase of the CAD-4 diffractometer under grant No. DPT/TBAG1 of the Scientific and Technical Research Council of Turkey.

references
References top

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Amiraslanov, I. R., Mamedov, Kh. S., Movsumov, E. M., Musaev, F. N. & Nadzhafov, G. N. (1979). Zh. Strukt. Khim. 20, 1075–1080. (In Russian.)

Antolini, L., Battaglia, L. P., Corradi, A. B., Marcotrigiano, G., Menabue, L., Pellacani, G. C. & Saladini, M. (1982). Inorg. Chem. 21, 1391–1395.

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