metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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catena-Poly[[[cis-aqua­di­bromido­cobalt(II)]-μ-(pyrazine-2-carb­­oxy­lic acid)-κ3N1,O:N4] monohydrate]

aDepartment of Chemistry, York University, Toronto, Ontario, Canada M3J 1P3
*Correspondence e-mail: blever@yorku.ca

(Received 11 November 2011; accepted 15 November 2011; online 23 November 2011)

The title compound, {[CoBr2(C5H4N2O2)(H2O)]·H2O}n, is a one-dimensional coordination polymer which crystallizes as a monohydrate. The asymmetric unit contains one CoII atom in a distorted octa­hedral geometry, forming a chain parallel to [010] with the pyrazine carb­oxy­lic acid ligands coordinating on one side in a bidentate fashion through one N and one O atom, and in a monodentate fashion through a N atom, with N atoms trans, and with both ligands lying in the same plane. The bromide atoms are cis to each other, while a water mol­ecule occupies the final octa­hedral coordination site. The chains are linked together though an O—H⋯Br hydrogen bonding network, and are further stabilized by an O—H⋯Br and O—H⋯O hydrogen-bonding framework with the solvent water mol­ecule.

Related literature

For the synthesis of related compounds, see: Gao et al. (2007[Gao, Y.-X., Wang, L.-B., Niu, Y.-L. & Hao, L.-J. (2007). Acta Cryst. E63, m1882.]) and references therein. For other examples of linear coordin­ation polymers utilizing pyrazine derivatives, see: Mao et al. (1996[Mao, L., Rettig, S. J., Thompson, R. C., Trotter, J., Xia, S. (1996). Can. J. Chem. 74, 433-444.]).

[Scheme 1]

Experimental

Crystal data
  • [CoBr2(C5H4N2O2)(H2O)]·H2O

  • Mr = 378.88

  • Monoclinic, P 21 /c

  • a = 6.9367 (3) Å

  • b = 13.9983 (3) Å

  • c = 11.1446 (5) Å

  • β = 106.043 (2)°

  • V = 1040.02 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 9.32 mm−1

  • T = 150 K

  • 0.18 × 0.16 × 0.06 mm

Data collection
  • Bruker–Nonius KappaCCD diffractometer

  • Absorption correction: multi-scan (SORTAV; Blessing, 1995[Blessing, R. H. (1995). Acta Cryst. A51, 33-38.]) Tmin = 0.399, Tmax = 0.962

  • 7275 measured reflections

  • 2375 independent reflections

  • 2013 reflections with I > 2σ(I)

  • Rint = 0.055

Refinement
  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.088

  • S = 1.04

  • 2375 reflections

  • 147 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.77 e Å−3

  • Δρmin = −1.25 e Å−3

Table 1
Selected geometric parameters (Å, °)

Co1—O1 2.073 (3)
Co1—N1 2.139 (3)
Co1—N2 2.179 (3)
Co1—O2 2.185 (2)
Co1—Br1 2.5499 (6)
Co1—Br2 2.5522 (6)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1A⋯Br1i 0.91 (5) 2.31 (5) 3.212 (3) 169 (4)
O1—H1B⋯Br2ii 0.87 (5) 2.39 (5) 3.251 (3) 173 (5)
O1W—H1W⋯Br1iii 0.75 (6) 2.68 (6) 3.390 (3) 159 (6)
O1W—H2W⋯Br2iv 0.76 (6) 2.57 (6) 3.335 (4) 176 (7)
O3—H3W⋯O1W 0.81 (5) 1.76 (5) 2.543 (5) 166 (6)
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) x+1, y, z; (iii) x+1, y, z+1; (iv) -x+1, -y+1, -z+2.

Data collection: COLLECT (Nonius, 2002[Nonius (2002). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO-SMN; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

The title compound (I) forms a linear 1-D coordination polymer aligned along b, with pyrazine carboxylic acid ligands linking CoII metal centres together in a bidentate fashion to one cobalt through N and O atoms, and in a monodentate fashion through the remaining N atom, with N atoms trans to each other, and neighboring pyrazine rings within the same plane. The two bromide anions are coordinated in a cis arrangement, with a water molecule completing the distorted octahedral geometry about the CoII. The asymmetric unit includes only a single monomer, with the 21 screw axis generating the neighboring 'inverted' linked monomer.The Co–N bonds average 2.16 Å, while the Co–Opz bond length is 2.18 Å. The Co–Br bonds are essentially identical at 2.55 Å.

Linear chains directly interact with each other through hydrogen bonding between the coordinated water, and bromide ligands. The single water solvate is involved heavily in the hydrogen bonding network interacting with both bromide anions, as well as the carboxylic acid group further stabilizing the crystal structure.

Related literature top

For the synthesis of related compounds, see: Gao et al. (2007) and references therein. For other examples of linear coordination polymers utilizing pyrazine derivatives, see: Mao et al. (1996).

Experimental top

In a synthesis designed to form mer-tris(pyrazine carboxylato)cobalt(III), CoBr2.6(H2O) was dissolved in methanol at room temperature to which three equivalents of pyrazine carboxylic acid was added. The initial red precipitate that formed almost immediately and was identified as mer-tris(pyrazine carboxylato)cobalt(III) bromide was removed by filtration. To the mother liquor was added an equal volume of water. Subsequently, the blue solution was allowed to stand for 2 months at room temperature allowing (I) to crystallize by slow evaporation yielding bright pink prismatic crystals suitable for X-ray diffraction. Attempts to remake (I) via more rational routes using CoBr2.6(H2O) and one equivalent of pyrazine carboxylic acid were not successful.

Refinement top

All H atoms attached to C atoms were added in ideal locations, and constrained to ride on the parent atoms with Uiso = 1.2Ueq(C). The H atoms attached to O atoms were located in the electron density difference map, and, with the exception of H1B were allowed to refine spatially and thermally. H1B was restrained to be 0.82 ± 0.02 Å from O1.

Structure description top

The title compound (I) forms a linear 1-D coordination polymer aligned along b, with pyrazine carboxylic acid ligands linking CoII metal centres together in a bidentate fashion to one cobalt through N and O atoms, and in a monodentate fashion through the remaining N atom, with N atoms trans to each other, and neighboring pyrazine rings within the same plane. The two bromide anions are coordinated in a cis arrangement, with a water molecule completing the distorted octahedral geometry about the CoII. The asymmetric unit includes only a single monomer, with the 21 screw axis generating the neighboring 'inverted' linked monomer.The Co–N bonds average 2.16 Å, while the Co–Opz bond length is 2.18 Å. The Co–Br bonds are essentially identical at 2.55 Å.

Linear chains directly interact with each other through hydrogen bonding between the coordinated water, and bromide ligands. The single water solvate is involved heavily in the hydrogen bonding network interacting with both bromide anions, as well as the carboxylic acid group further stabilizing the crystal structure.

For the synthesis of related compounds, see: Gao et al. (2007) and references therein. For other examples of linear coordination polymers utilizing pyrazine derivatives, see: Mao et al. (1996).

Computing details top

Data collection: COLLECT (Nonius, 2002); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); 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, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. A view of (I) with atom numbering scheme showing the molecular structure and intra- and intermolecular H bonding present. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Crystal packing diagram of (I) showing layers of (I) interacting via the H bonding network. Displacement ellipsoids are drawn at the 50% probability level.
catena-Poly[[[cis-aquadibromidocobalt(II)]-µ- (pyrazine-2-carboxylic acid)-κ3N1,O:N4] monohydrate] top
Crystal data top
[CoBr2(C5H4N2O2)(H2O)]·H2OF(000) = 724
Mr = 378.88Dx = 2.42 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3286 reflections
a = 6.9367 (3) Åθ = 2.6–27.5°
b = 13.9983 (3) ŵ = 9.32 mm1
c = 11.1446 (5) ÅT = 150 K
β = 106.043 (2)°Prism, pink
V = 1040.02 (7) Å30.18 × 0.16 × 0.06 mm
Z = 4
Data collection top
Bruker–Nonius KappaCCD
diffractometer
2375 independent reflections
Radiation source: fine-focus sealed tube2013 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.055
φ scans and ω scans with κ offsetsθmax = 27.5°, θmin = 2.9°
Absorption correction: multi-scan
(SORTAV; Blessing, 1995)
h = 88
Tmin = 0.399, Tmax = 0.962k = 1718
7275 measured reflectionsl = 1414
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)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.088H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.051P)2]
where P = (Fo2 + 2Fc2)/3
2375 reflections(Δ/σ)max < 0.001
147 parametersΔρmax = 0.77 e Å3
1 restraintΔρmin = 1.25 e Å3
Crystal data top
[CoBr2(C5H4N2O2)(H2O)]·H2OV = 1040.02 (7) Å3
Mr = 378.88Z = 4
Monoclinic, P21/cMo Kα radiation
a = 6.9367 (3) ŵ = 9.32 mm1
b = 13.9983 (3) ÅT = 150 K
c = 11.1446 (5) Å0.18 × 0.16 × 0.06 mm
β = 106.043 (2)°
Data collection top
Bruker–Nonius KappaCCD
diffractometer
2375 independent reflections
Absorption correction: multi-scan
(SORTAV; Blessing, 1995)
2013 reflections with I > 2σ(I)
Tmin = 0.399, Tmax = 0.962Rint = 0.055
7275 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0361 restraint
wR(F2) = 0.088H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.77 e Å3
2375 reflectionsΔρmin = 1.25 e Å3
147 parameters
Special details top

Experimental. multi-scan from symmetry-related measurements Sortav (Blessing 1995)

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
Co10.43042 (7)0.60139 (3)0.71677 (4)0.01247 (14)
Br10.21778 (6)0.59962 (2)0.49002 (3)0.01792 (13)
Br20.14725 (6)0.61738 (3)0.82087 (3)0.02000 (13)
O10.6859 (4)0.5836 (2)0.6571 (3)0.0203 (6)
O20.6433 (4)0.62621 (18)0.8992 (2)0.0154 (5)
O30.8202 (4)0.7413 (2)1.0224 (2)0.0212 (6)
N10.4772 (4)0.7525 (2)0.7222 (3)0.0138 (6)
N20.4431 (4)0.4469 (2)0.7415 (3)0.0141 (6)
C10.6070 (5)0.7858 (2)0.8275 (3)0.0135 (7)
C20.3514 (5)0.3823 (3)0.6545 (3)0.0140 (7)
H20.25740.40340.57990.017*
C30.5688 (6)0.4125 (3)0.8461 (3)0.0169 (8)
H30.63360.45580.91010.020*
C40.3927 (6)0.8159 (3)0.6360 (3)0.0161 (7)
H40.30320.79460.55990.019*
C50.6938 (5)0.7099 (3)0.9208 (3)0.0136 (7)
H1A0.701 (7)0.527 (4)0.619 (5)0.040 (14)*
H1B0.802 (5)0.597 (4)0.700 (6)0.07 (2)*
H3W0.854 (7)0.695 (4)1.066 (5)0.035 (14)*
O1W0.9753 (5)0.6131 (3)1.1815 (3)0.0282 (7)
H1W1.020 (9)0.625 (4)1.249 (6)0.038 (17)*
H2W0.952 (7)0.560 (4)1.184 (5)0.035 (15)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0156 (3)0.0113 (3)0.0094 (3)0.00003 (17)0.0017 (2)0.00028 (17)
Br10.0230 (2)0.0170 (2)0.0106 (2)0.00181 (13)0.00064 (16)0.00216 (12)
Br20.0186 (2)0.0276 (2)0.0140 (2)0.00205 (14)0.00479 (16)0.00451 (14)
O10.0186 (16)0.0208 (15)0.0217 (16)0.0007 (11)0.0061 (13)0.0048 (11)
O20.0205 (14)0.0127 (13)0.0113 (13)0.0008 (10)0.0013 (11)0.0011 (9)
O30.0286 (16)0.0173 (15)0.0122 (13)0.0009 (11)0.0035 (12)0.0001 (11)
N10.0162 (16)0.0138 (15)0.0127 (14)0.0007 (12)0.0061 (13)0.0010 (12)
N20.0212 (17)0.0133 (15)0.0093 (14)0.0011 (12)0.0064 (13)0.0001 (11)
C10.0177 (19)0.0142 (18)0.0092 (17)0.0019 (14)0.0045 (15)0.0010 (13)
C20.016 (2)0.0163 (18)0.0100 (17)0.0005 (13)0.0039 (15)0.0013 (13)
C30.021 (2)0.0177 (19)0.0112 (18)0.0041 (15)0.0034 (16)0.0028 (14)
C40.021 (2)0.0163 (19)0.0093 (16)0.0004 (14)0.0014 (15)0.0018 (14)
C50.0141 (19)0.019 (2)0.0086 (16)0.0027 (14)0.0042 (14)0.0010 (13)
O1W0.037 (2)0.0257 (19)0.0166 (17)0.0032 (14)0.0020 (15)0.0060 (13)
Geometric parameters (Å, º) top
Co1—O12.073 (3)N1—C11.349 (4)
Co1—N12.139 (3)N2—C31.337 (5)
Co1—N22.179 (3)N2—C21.350 (5)
Co1—O22.185 (2)C1—C2i1.384 (5)
Co1—Br12.5499 (6)C1—C51.493 (5)
Co1—Br22.5522 (6)C2—H20.9500
O1—H1A0.92 (5)C3—C4ii1.382 (5)
O1—H1B0.84 (2)C3—H30.9500
O2—C51.227 (4)C4—H40.9500
O3—C51.302 (4)O1W—H1W0.75 (6)
O3—H3W0.80 (5)O1W—H2W0.77 (6)
N1—C41.320 (5)
O1—Co1—N189.51 (11)C4—N1—Co1127.6 (2)
O1—Co1—N285.02 (11)C1—N1—Co1115.2 (2)
N1—Co1—N2167.90 (12)C3—N2—C2116.7 (3)
O1—Co1—O284.25 (10)C3—N2—Co1117.5 (2)
N1—Co1—O276.01 (10)C2—N2—Co1125.4 (2)
N2—Co1—O292.67 (10)N1—C1—C2i121.7 (3)
O1—Co1—Br189.57 (8)N1—C1—C5113.8 (3)
N1—Co1—Br194.55 (8)C2i—C1—C5124.5 (3)
N2—Co1—Br196.20 (8)N2—C2—C1ii120.7 (3)
O2—Co1—Br1168.71 (7)N2—C2—H2119.6
O1—Co1—Br2171.91 (8)C1ii—C2—H2119.6
N1—Co1—Br291.74 (8)N2—C3—C4ii122.2 (3)
N2—Co1—Br292.21 (8)N2—C3—H3118.9
O2—Co1—Br288.30 (7)C4ii—C3—H3118.9
Br1—Co1—Br298.29 (2)N1—C4—C3i121.5 (3)
Co1—O1—H1A118 (3)N1—C4—H4119.2
Co1—O1—H1B125 (5)C3i—C4—H4119.2
H1A—O1—H1B104 (5)O2—C5—O3125.4 (3)
C5—O2—Co1114.6 (2)O2—C5—C1120.3 (3)
C5—O3—H3W106 (4)O3—C5—C1114.2 (3)
C4—N1—C1117.1 (3)H1W—O1W—H2W102 (5)
Symmetry codes: (i) x+1, y+1/2, z+3/2; (ii) x+1, y1/2, z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···Br1iii0.91 (5)2.31 (5)3.212 (3)169 (4)
O1—H1B···Br2iv0.87 (5)2.39 (5)3.251 (3)173 (5)
O1W—H1W···Br1v0.75 (6)2.68 (6)3.390 (3)159 (6)
O1W—H2W···Br2vi0.76 (6)2.57 (6)3.335 (4)176 (7)
O3—H3W···O1W0.81 (5)1.76 (5)2.543 (5)166 (6)
Symmetry codes: (iii) x+1, y+1, z+1; (iv) x+1, y, z; (v) x+1, y, z+1; (vi) x+1, y+1, z+2.

Experimental details

Crystal data
Chemical formula[CoBr2(C5H4N2O2)(H2O)]·H2O
Mr378.88
Crystal system, space groupMonoclinic, P21/c
Temperature (K)150
a, b, c (Å)6.9367 (3), 13.9983 (3), 11.1446 (5)
β (°) 106.043 (2)
V3)1040.02 (7)
Z4
Radiation typeMo Kα
µ (mm1)9.32
Crystal size (mm)0.18 × 0.16 × 0.06
Data collection
DiffractometerBruker–Nonius KappaCCD
Absorption correctionMulti-scan
(SORTAV; Blessing, 1995)
Tmin, Tmax0.399, 0.962
No. of measured, independent and
observed [I > 2σ(I)] reflections
7275, 2375, 2013
Rint0.055
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.088, 1.04
No. of reflections2375
No. of parameters147
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.77, 1.25

Computer programs: COLLECT (Nonius, 2002), DENZO-SMN (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Selected geometric parameters (Å, º) top
Co1—O12.073 (3)Co1—O22.185 (2)
Co1—N12.139 (3)Co1—Br12.5499 (6)
Co1—N22.179 (3)Co1—Br22.5522 (6)
O1—Co1—N189.51 (11)N2—Co1—Br196.20 (8)
O1—Co1—N285.02 (11)O2—Co1—Br1168.71 (7)
N1—Co1—N2167.90 (12)O1—Co1—Br2171.91 (8)
O1—Co1—O284.25 (10)N1—Co1—Br291.74 (8)
N1—Co1—O276.01 (10)N2—Co1—Br292.21 (8)
N2—Co1—O292.67 (10)O2—Co1—Br288.30 (7)
O1—Co1—Br189.57 (8)Br1—Co1—Br298.29 (2)
N1—Co1—Br194.55 (8)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···Br1i0.91 (5)2.31 (5)3.212 (3)169 (4)
O1—H1B···Br2ii0.87 (5)2.39 (5)3.251 (3)173 (5)
O1W—H1W···Br1iii0.75 (6)2.68 (6)3.390 (3)159 (6)
O1W—H2W···Br2iv0.76 (6)2.57 (6)3.335 (4)176 (7)
O3—H3W···O1W0.81 (5)1.76 (5)2.543 (5)166 (6)
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+1, y, z; (iii) x+1, y, z+1; (iv) x+1, y+1, z+2.
 

Acknowledgements

The authors thank Dr Alan J. Lough for acquiring the X-ray diffraction data. Financial support for this work was provided by the Natural Sciences and Engineering Research Council of Canada (NSERC). CD thanks the NSERC and the Government of Ontario for post-graduate scholarships.

References

First citationBlessing, R. H. (1995). Acta Cryst. A51, 33–38.  CrossRef CAS Web of Science IUCr Journals Google Scholar
First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
First citationFarrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.  CrossRef CAS IUCr Journals Google Scholar
First citationGao, Y.-X., Wang, L.-B., Niu, Y.-L. & Hao, L.-J. (2007). Acta Cryst. E63, m1882.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationMao, L., Rettig, S. J., Thompson, R. C., Trotter, J., Xia, S. (1996). Can. J. Chem. 74, 433–444.  CrossRef CAS Web of Science Google Scholar
First citationNonius (2002). COLLECT. Nonius BV, Delft, The Netherlands.  Google Scholar
First citationOtwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307–326. New York: Academic Press.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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