research communications\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 71| Part 4| April 2015| Pages 339-341

Crystal structure of catena-poly[[di­aqua­bis­­(4-formyl­benzoato-κO1)cobalt(II)]-μ-pyrazine-κ2N:N′]

CROSSMARK_Color_square_no_text.svg

aDepartment of Physics, Hacettepe University, 06800 Beytepe, Ankara, Turkey, bDepartment of Chemistry, Kafkas University, 36100 Kars, Turkey, and cAksaray University, Department of Physics, 68100, Aksaray, Turkey
*Correspondence e-mail: merzifon@hacettepe.edu.tr

Edited by M. Weil, Vienna University of Technology, Austria (Received 18 February 2015; accepted 26 February 2015; online 4 March 2015)

In the title polymeric compound, [Co(C8H5O3)2(C4H4N2)(H2O)2]n, the CoII atom is located on a twofold rotation axis and has a slightly distorted octa­hedral coordination sphere. In the equatorial plane, it is coordinated by two carboxyl­ate O atoms of two symmetry-related monodentate formyl­benzoate anions and by two N atoms of two bridging pyrazine ligands. The latter are bis­ected by the twofold rotation axis. The axial positions are occupied by two O atoms of the coordinating water mol­ecules. In the formyl­benzoate anion, the carboxyl­ate group is twisted away from the attached benzene ring by 7.50 (8)°, while the benzene and pyrazine rings are oriented at a dihedral angle of 64.90 (4)°. The pyrazine ligands bridge the CoII cations, forming linear chains running along the b-axis direction. Strong intra­molecular O—H⋯O hydrogen bonds link the water mol­ecules to the carboxyl­ate O atoms. In the crystal, weak O—Hwater⋯Owater hydrogen bonds link adjacent chains into layers parallel to the bc plane. The layers are linked via C—Hpyrazine⋯Oform­yl hydrogen bonds, forming a three-dimensional network. There are also weak C—H⋯π inter­actions present.

1. Chemical context

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 (Adiwidjaja et al., 1978[Adiwidjaja, G., Rossmanith, E. & Küppers, H. (1978). Acta Cryst. B34, 3079-3083.]; Antsyshkina et al., 1980[Antsyshkina, A. S., Chiragov, F. M. & Poray-Koshits, M. A. (1980). Koord. Khim. 15, 1098-1103.]; Nadzhafov et al., 1981[Nadzhafov, G. N., Shnulin, A. N. & Mamedov, Kh. S. (1981). Zh. Strukt. Khim. 22, 124-128.]; Shnulin et al., 1981[Shnulin, A. N., Nadzhafov, G. N., Amiraslanov, I. R., Usubaliev, B. T. & Mamedov, Kh. S. (1981). Koord. Khim. 7, 1409-1416.]). Transition metal complexes with biochemically active ligands frequently show inter­esting physical and/or chemical properties and, as a result, they may find applications in biological systems (Antolini et al., 1982[Antolini, L., Battaglia, L. P., Corradi, A. B., Marcotrigiano, G., Menabue, L., Pellacani, G. C. & Saladini, M. (1982). Inorg. Chem. 21, 1391-1395.]). Some benzoic acid derivatives, such as 4-amino­benzoic acid, have been extensively reported in coordination chemistry, as bifunctional organic ligands, due to the varieties of their coordination modes (Chen & Chen, 2002[Chen, H. J. & Chen, X. M. (2002). Inorg. Chim. Acta, 329, 13-21.]; Amiraslanov et al., 1979[Amiraslanov, I. R., Mamedov, Kh. S., Movsumov, E. M., Musaev, F. N. & Nadzhafov, G. N. (1979). Zh. Strukt. Khim. 20, 1075-1080.]; Hauptmann et al., 2000[Hauptmann, R., Kondo, M. & Kitagawa, S. (2000). Z. Kristallogr. New Cryst. Struct. 215, 169-172.]).

In this context, we report the synthesis and crystal structure of the title compound, [Co(C8H5O3)2(C4H4N2)(H2O)2]n, which is isotypic with its CuII (Çelik et al., 2014a[Çelik, F., Dilek, N., Çaylak Delibaş, N., Necefoğlu, H. & Hökelek, T. (2014a). Acta Cryst. E70, m4-m5.]) and NiII (Çelik et al., 2014b[Çelik, F., Dilek, N., Çaylak Delibaş, N., Necefoğlu, H. & Hökelek, T. (2014b). Acta Cryst. E70, m65-m66.]) analogues.

2. Structural commentary

The asymmetric unit of the title compound contains a CoII ion, one formyl­benzoate (FB) anion, one water mol­ecule and half of a pyrazine mol­ecule. Atoms N1 and N2 of the pyrazine ligand and Co1 are located on a twofold rotation axis (Fig. 1[link]). The pyrazine ligands bridge adjacent CoII ions, forming polymeric chains running along the b-axis direction (Fig. 2[link]). The distance between symmetry-related CoII ions [Co1⋯Co1iii; symmetry code: (iii) x, y + 1, z] is 7.1193 (4) Å.

[Scheme 1]
[Figure 1]
Figure 1
A view of the coordination environment around the CoII atom of the title mol­ecule, showing the atom labelling. Displacement ellipsoids are drawn at the 50% probability level. The twofold rotation axis bis­ects atoms Co1, N1 and N2. Non-labelled atoms are generated by the symmetry code −x + 2, y, −z + [{3\over 2}].
[Figure 2]
Figure 2
A partial view of the crystal packing of the title compound.

The equatorial plane of the CoIIO4N2 coordination sphere is composed of two carboxyl­ate O atoms [O1 and O1i; symmetry code: (i) 2 − x, y, [{3\over 2}] − z] of two symmetry-related monodentate formyl­benzoate anions and two N atoms [N1 and N2ii; symmetry code: (ii) x, −1 + y, z] of two bridging pyrazine ligands, which are bis­ected by the twofold rotation axis. The axial positions are occupied by two O atoms (O4 and O4i) of the coordinating water mol­ecules.

The near equality of the C1—O1 [1.272 (2) Å] and C1—O2 [1.245 (2) Å] bonds in the carboxyl­ate group indicates a delocalized bonding arrangement, rather than localized single and double bonds. The Co—N bond length is 2.165 (9) Å, while the Co—O bond lengths are 2.0551 (9) Å (for benzoate oxygen) and 2.1491 (11) Å (for water oxygen), close to standard values. The Co1 atom is displaced by 0.1034 (2) Å from the mean plane of the carboxyl­ate group (O1/C1/O2). The dihedral angle between the carboxyl­ate group and the adjacent benzene ring A (C2–C7) is 7.50 (8)°, while the benzene and pyrazine rings are oriented at a dihedral angle of 64.90 (4)°.

3. Supra­molecular features

Strong intra­molecular O—H⋯O hydrogen bonds (Table 1[link]) link the water mol­ecules to the non-coordinating carboxyl­ate oxygen atoms. In the crystal, weak O—Hwater⋯Owater hydrogen bonds (Table 1[link]) link adjacent chains into layers parallel to the bc plane. The layers are linked via C—Hpyrazine⋯Oform­yl hydrogen bonds, forming a three-dimensional network (Fig. 3[link]). There are also weak C—H⋯π inter­actions present (Table 1[link]).

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of ring A (C2–C7).

D—H⋯A D—H H⋯A DA D—H⋯A
O4—H41⋯O2 0.89 (3) 1.72 (3) 2.5909 (16) 164 (2)
O4—H42⋯O4i 0.71 (3) 2.63 (3) 2.958 (2) 111 (2)
C10—H10⋯O3ii 0.93 2.46 3.320 (2) 154
C7—H7⋯Cg1iii 0.93 2.65 3.4216 (15) 142
Symmetry codes: (i) -x+2, -y, -z+1; (ii) [-x+{\script{3\over 2}}, -y+{\script{1\over 2}}, -z+2]; (iii) [x, -y, z-{\script{1\over 2}}].
[Figure 3]
Figure 3
Part of the crystal structure. Inter­molecular hydrogen bonds are shown as dashed lines. Non-bonding H atoms have been omitted for clarity.

4. Refinement

The experimental details including the crystal data, data collection and refinement are summarized in Table 2[link]. Atoms H41 and H42 (for H2O) were located in a difference Fourier map and were refined freely. The methine H atom was also located in a difference Fourier map and the C—H distance restrained to 0.984 (13) Å. The aromatic C-bound H atoms were positioned geometrically with C—H = 0.93 Å, and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C).

Table 2
Experimental details

Crystal data
Chemical formula [Co(C8H5O3)2(C4H4N2)(H2O)2]
Mr 473.29
Crystal system, space group Monoclinic, C2/c
Temperature (K) 296
a, b, c (Å) 22.1623 (6), 7.1193 (2), 12.2911 (3)
β (°) 94.432 (1)
V3) 1933.49 (9)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.94
Crystal size (mm) 0.47 × 0.22 × 0.11
 
Data collection
Diffractometer Bruker SMART BREEZE CCD
Absorption correction Multi-scan (SADABS; Bruker, 2012[Bruker (2012). APEX2, SAINT and SADABS. Bruker AXS Inc. Madison, Wisconsin, USA.])
Tmin, Tmax 0.830, 0.914
No. of measured, independent and observed [I > 2σ(I)] reflections 27023, 2427, 2336
Rint 0.024
(sin θ/λ)max−1) 0.668
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.025, 0.071, 1.06
No. of reflections 2427
No. of parameters 154
No. of restraints 1
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.35, −0.34
Computer programs: APEX2 and SAINT (Bruker, 2012[Bruker (2012). APEX2, SAINT and SADABS. Bruker AXS Inc. Madison, Wisconsin, USA.]), SHELXS97 and SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), ORTEP-3 for Windows and WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

5. Synthesis and crystallization

The title compound was prepared by the reaction of CoSO4·7H2O (1.40 g, 5 mmol) in H2O (25 ml) and pyrazine (0.40 g, 5 mmol) in H2O (25 ml) with sodium 4-formyl­benzoate (1.72 g, 10 mmol) in H2O (70 ml) at room temperature. The mixture was filtered and set aside to crystallize at ambient temperature for one week, giving orange single crystals.

Supporting information


Computing details top

Data collection: APEX2 (Bruker, 2012); cell refinement: SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); 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, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

catena-Poly[[diaquabis(4-formylbenzoato-κO1)cobalt(II)]-µ-pyrazine-κ2N:N'] top
Crystal data top
[Co(C8H5O3)2(C4H4N2)(H2O)2]F(000) = 972
Mr = 473.29Dx = 1.626 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 9866 reflections
a = 22.1623 (6) Åθ = 2.4–28.3°
b = 7.1193 (2) ŵ = 0.94 mm1
c = 12.2911 (3) ÅT = 296 K
β = 94.432 (1)°Block, orange
V = 1933.49 (9) Å30.47 × 0.22 × 0.11 mm
Z = 4
Data collection top
Bruker SMART BREEZE CCD
diffractometer
2427 independent reflections
Radiation source: fine-focus sealed tube2336 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
φ and ω scansθmax = 28.4°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2012)
h = 2929
Tmin = 0.830, Tmax = 0.914k = 99
27023 measured reflectionsl = 1616
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)] = 0.025Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.071H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.0409P)2 + 1.5712P]
where P = (Fo2 + 2Fc2)/3
2427 reflections(Δ/σ)max = 0.001
154 parametersΔρmax = 0.35 e Å3
1 restraintΔρmin = 0.34 e Å3
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
Co11.00000.05145 (3)0.75000.01998 (9)
O10.91572 (4)0.04830 (13)0.80894 (9)0.0276 (2)
O20.86274 (5)0.17780 (18)0.66579 (9)0.0402 (3)
O30.60114 (6)0.1312 (3)0.95577 (12)0.0651 (4)
O40.96115 (5)0.06701 (18)0.58454 (9)0.0352 (2)
H410.9245 (12)0.104 (4)0.600 (2)0.058 (6)*
H420.9564 (12)0.019 (4)0.555 (2)0.066 (8)*
N11.00000.2518 (2)0.75000.0247 (3)
N21.00000.6436 (2)0.75000.0235 (3)
C10.86731 (5)0.11157 (17)0.75983 (11)0.0240 (2)
C20.81095 (5)0.10250 (17)0.82116 (10)0.0226 (2)
C30.81105 (6)0.0089 (2)0.92052 (11)0.0268 (2)
H30.84670.04390.95180.032*
C40.75794 (6)0.0058 (2)0.97289 (11)0.0301 (3)
H40.75800.06821.03940.036*
C50.70463 (6)0.0726 (2)0.92617 (12)0.0292 (3)
C60.70446 (6)0.1685 (2)0.82755 (12)0.0307 (3)
H60.66890.22220.79670.037*
C70.75745 (6)0.18340 (19)0.77557 (11)0.0271 (3)
H70.75740.24780.70980.032*
C80.64849 (8)0.0553 (3)0.98296 (15)0.0430 (4)
H80.6472 (7)0.029 (2)1.0463 (12)0.021 (4)*
C90.97461 (6)0.35053 (18)0.82681 (11)0.0287 (3)
H90.95630.28690.88150.034*
C100.97486 (7)0.54530 (17)0.82719 (12)0.0282 (3)
H100.95710.60900.88250.034*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.01683 (12)0.01603 (12)0.02763 (14)0.0000.00520 (8)0.000
O10.0180 (4)0.0288 (5)0.0366 (5)0.0022 (3)0.0058 (4)0.0040 (4)
O20.0284 (5)0.0584 (7)0.0351 (5)0.0116 (5)0.0103 (4)0.0128 (5)
O30.0296 (6)0.1092 (13)0.0583 (8)0.0015 (7)0.0149 (5)0.0049 (9)
O40.0299 (5)0.0449 (6)0.0312 (5)0.0052 (5)0.0051 (4)0.0083 (5)
N10.0217 (7)0.0178 (6)0.0353 (8)0.0000.0065 (6)0.000
N20.0242 (7)0.0172 (6)0.0301 (7)0.0000.0078 (6)0.000
C10.0197 (5)0.0204 (5)0.0324 (6)0.0004 (4)0.0059 (4)0.0013 (5)
C20.0193 (5)0.0218 (5)0.0270 (6)0.0006 (4)0.0039 (4)0.0022 (4)
C30.0224 (6)0.0303 (6)0.0272 (6)0.0003 (5)0.0008 (5)0.0012 (5)
C40.0312 (7)0.0337 (7)0.0259 (6)0.0040 (6)0.0048 (5)0.0022 (5)
C50.0236 (6)0.0332 (7)0.0317 (6)0.0046 (5)0.0086 (5)0.0055 (5)
C60.0207 (6)0.0367 (7)0.0351 (7)0.0048 (5)0.0038 (5)0.0002 (6)
C70.0234 (6)0.0308 (6)0.0274 (6)0.0050 (5)0.0048 (5)0.0036 (5)
C80.0316 (8)0.0576 (11)0.0417 (8)0.0079 (7)0.0152 (6)0.0035 (7)
C90.0318 (6)0.0211 (6)0.0349 (7)0.0002 (5)0.0137 (5)0.0036 (5)
C100.0332 (7)0.0210 (6)0.0321 (7)0.0016 (5)0.0141 (5)0.0009 (5)
Geometric parameters (Å, º) top
Co1—O12.0551 (9)C2—C11.5093 (17)
Co1—O1i2.0551 (9)C2—C31.3911 (18)
Co1—O42.1491 (11)C2—C71.3961 (17)
Co1—O4i2.1491 (11)C3—H30.9300
Co1—N12.1588 (15)C4—C31.3884 (18)
Co1—N2ii2.1714 (15)C4—H40.9300
O1—C11.2721 (16)C5—C41.390 (2)
O2—C11.2451 (17)C5—C61.391 (2)
O3—C81.205 (2)C5—C81.478 (2)
O4—H410.89 (3)C6—H60.9300
O4—H420.71 (3)C7—C61.3836 (18)
N1—C91.3357 (15)C7—H70.9300
N1—C9i1.3357 (15)C8—H80.984 (13)
N2—Co1iii2.1714 (15)C9—H90.9300
N2—C101.3347 (15)C10—C91.3866 (19)
N2—C10i1.3347 (15)C10—H100.9300
O1—Co1—O1i178.75 (5)C3—C2—C1120.92 (11)
O1—Co1—O491.46 (4)C3—C2—C7119.58 (12)
O1i—Co1—O488.60 (4)C7—C2—C1119.46 (11)
O1—Co1—O4i88.60 (4)C2—C3—H3120.0
O1i—Co1—O4i91.46 (4)C4—C3—C2119.94 (12)
O1—Co1—N189.38 (3)C4—C3—H3120.0
O1i—Co1—N189.38 (3)C3—C4—C5120.15 (13)
O1—Co1—N2ii90.62 (3)C3—C4—H4119.9
O1i—Co1—N2ii90.62 (3)C5—C4—H4119.9
O4—Co1—O4i174.09 (7)C4—C5—C6120.13 (12)
O4—Co1—N192.96 (4)C4—C5—C8119.41 (14)
O4i—Co1—N192.96 (4)C6—C5—C8120.46 (14)
O4—Co1—N2ii87.04 (4)C5—C6—H6120.2
O4i—Co1—N2ii87.04 (4)C7—C6—C5119.67 (12)
N1—Co1—N2ii180.000 (1)C7—C6—H6120.2
C1—O1—Co1125.81 (9)C2—C7—H7119.7
Co1—O4—H4196.6 (15)C6—C7—C2120.52 (12)
Co1—O4—H42118 (2)C6—C7—H7119.7
H41—O4—H42105 (3)O3—C8—C5125.34 (17)
C9—N1—Co1121.75 (8)O3—C8—H8114.5 (10)
C9i—N1—Co1121.75 (8)C5—C8—H8120.1 (10)
C9—N1—C9i116.49 (15)N1—C9—C10121.79 (12)
C10—N2—Co1iii121.61 (8)N1—C9—H9119.1
C10i—N2—Co1iii121.61 (8)C10—C9—H9119.1
C10—N2—C10i116.79 (15)N2—C10—C9121.57 (12)
O1—C1—C2116.62 (11)N2—C10—H10119.2
O2—C1—O1125.42 (12)C9—C10—H10119.2
O2—C1—C2117.96 (11)
O4—Co1—O1—C123.45 (11)C3—C2—C1—O17.53 (18)
O4i—Co1—O1—C1150.64 (11)C3—C2—C1—O2171.75 (13)
N1—Co1—O1—C1116.39 (10)C7—C2—C1—O1174.80 (12)
N2ii—Co1—O1—C163.61 (10)C7—C2—C1—O25.92 (18)
O1—Co1—N1—C935.39 (8)C1—C2—C3—C4176.79 (12)
O1i—Co1—N1—C9144.61 (8)C7—C2—C3—C40.9 (2)
O1—Co1—N1—C9i144.61 (8)C1—C2—C7—C6176.64 (12)
O1i—Co1—N1—C9i35.39 (8)C3—C2—C7—C61.1 (2)
O4—Co1—N1—C9126.82 (8)C5—C4—C3—C20.1 (2)
O4i—Co1—N1—C953.18 (8)C4—C5—C6—C70.8 (2)
O4—Co1—N1—C9i53.18 (8)C6—C5—C4—C31.0 (2)
O4i—Co1—N1—C9i126.82 (8)C8—C5—C4—C3179.86 (14)
Co1—O1—C1—O23.6 (2)C8—C5—C6—C7179.95 (14)
Co1—O1—C1—C2177.23 (8)C4—C5—C8—O3172.93 (18)
Co1—N1—C9—C10179.66 (10)C6—C5—C8—O36.3 (3)
C9i—N1—C9—C100.34 (10)C2—C7—C6—C50.2 (2)
Co1iii—N2—C10—C9179.66 (10)N2—C10—C9—N10.7 (2)
C10i—N2—C10—C90.34 (10)
Symmetry codes: (i) x+2, y, z+3/2; (ii) x, y1, z; (iii) x, y+1, z.
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of ring A (C2–C7).
D—H···AD—HH···AD···AD—H···A
O4—H41···O20.89 (3)1.72 (3)2.5909 (16)164 (2)
O4—H42···O4iv0.71 (3)2.63 (3)2.958 (2)111 (2)
C10—H10···O3v0.932.463.320 (2)154
C7—H7···Cg1vi0.932.653.4216 (15)142
Symmetry codes: (iv) x+2, y, z+1; (v) x+3/2, y+1/2, z+2; (vi) x, y, z1/2.
 

Acknowledgements

The authors acknowledge the Aksaray University Science and Technology Application and Research Center, Aksaray, Turkey, for the use of the Bruker SMART BREEZE CCD diffractometer (purchased under grant No. 2010K120480 of the State of Planning Organization). This work was supported financially by the Kafkas University Research Fund (grant No. 2012-FEF-12).

References

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Volume 71| Part 4| April 2015| Pages 339-341
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