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

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ISSN: 2056-9890

catena-Poly[[[di­aqua­iron(II)]-μ-pyrazine-2,3-di­carboxyl­ato] dihydrate]

aDepartment of Chemistry, Shangqiu Normal College, 476000 Shangqiu, Henan, People's Republic of China
*Correspondence e-mail: xuhyun1970@sohu.com

(Received 19 November 2007; accepted 29 November 2007; online 6 December 2007)

The crystal structure of the title compound, {[Fe(C6H2N2O4)(H2O)2]·2H2O}n, was synthesized by a diffusion method. It has a one-dimensional polymeric chain structure and the chains are further connected into a three-dimensional structure by hydrogen bonds. The FeII ion has a distorted octa­hedral coordination environment, with two N and two O atoms from the pyrazine-2,3-dicarboxyl­ate ligands in the equatorial plane and with two water mol­ecules in axial positions. The Fe atom lies on a crystallographic centre of symmetry and a twofold rotation axis passes through the pyrazine ring.

Related literature

For related literature, see: Kondo et al. (1999[Kondo, M., Okubo, T., Asami, A., Noro, S., Yoshitomi, T., Kitagawa, S., Ishii, T., Matsuzaka, H. & Sek, K. (1999). Angew. Chem. Int. Ed. 38, 140-143.]); Kitaura et al. (2002[Kitaura, R., Fujimoto, K., Noro, S., Kondo, M. & Kitagawa, S. (2002). Angew. Chem. Int. Ed. 41, 133-135.]); Zheng et al. (2002[Zheng, X.-J., Jin, L.-P. & Lu, S.-Z. (2002). Eur. J. Inorg. Chem. pp. 3356-3363.]); Mao et al. (1996[Mao, L., Rettig, S. J., Thompson, R. C., Trotter, J. & Xia, S.-H. (1996). Can. J. Chem. 74, 433-444.]); Castillo et al. (2003[Castillo, O., Beobide, G., Luque, A. & Román, P. (2003). Acta Cryst. E59, m800-m802.]); Konar et al. (2004[Konar, S., Manna, S. C., Zangrando, E. & Chaudhuri, N. R. (2004). Inorg. Chim. Acta, 357, 1593-1597.]); Muranishi & Okabe (2003[Muranishi, Y. & Okabe, N. (2003). Acta Cryst. E59, m883-m885.]); Richard et al. (1973[Richard, P., Tran Qui, D. & Bertaut, E. F. (1973). Acta Cryst. B29, 1111-1115.]); Xiang et al. (2004[Xiang, G.-Q., Zhu, N.-W., Hu, M.-L., Xiao, H.-P. & Chen, X.-X. (2004). Acta Cryst. E60, m647-m649.]); Zou et al. (1999[Zou, J.-Z., Xu, Z., Chen, W., Lo, K. M. & You, X.-Z. (1999). Polyhedron, 18, 1507-1512.]).

[Scheme 1]

Experimental

Crystal data
  • [Fe(C6H2N2O4)(H2O)2]·2H2O

  • Mr = 294.01

  • Monoclinic, C 2/c

  • a = 12.5650 (2) Å

  • b = 7.5158 (1) Å

  • c = 11.8314 (2) Å

  • β = 110.759 (1)°

  • V = 1044.77 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 1.48 mm−1

  • T = 298 (2) K

  • 0.23 × 0.20 × 0.18 mm

Data collection
  • Siemens SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.727, Tmax = 0.777

  • 5477 measured reflections

  • 1291 independent reflections

  • 1219 reflections with I > 2σ'(I)

  • Rint = 0.019

Refinement
  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.088

  • S = 1.03

  • 1291 reflections

  • 80 parameters

  • H-atom parameters constrained

  • Δρmax = 0.59 e Å−3

  • Δρmin = −0.70 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O4—H4A⋯O1i 0.85 2.17 2.890 (3) 142
O4—H4A⋯O2i 0.85 2.59 3.227 (3) 133
O4—H4B⋯O1ii 0.85 2.20 3.045 (3) 174
O3—H3A⋯O4iii 0.85 2.41 3.210 (3) 156
O3—H3B⋯O2iv 0.85 1.98 2.720 (2) 145
C3—H3⋯O2v 0.93 2.51 3.232 (3) 135
Symmetry codes: (i) [x, -y, z-{\script{1\over 2}}]; (ii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iv) [x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]; (v) x, y+1, z.

Data collection: SMART (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a[Sheldrick, G. M. (1997a). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a[Sheldrick, G. M. (1997a). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); molecular graphics: SHELXTL (Sheldrick, 1997b[Sheldrick, G. M. (1997b). SHELXTL. Version 5.1. Bruker AXS Inc., Madison, Wisconsin, USA.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Recently, the effective combination of coordination bond and hydrogen bond has been applied in the engineering study of inorganic-organic hybrid material and the construction of metal-organic coordination supramolecular complexes. The suitable organic ligand makes the complex not only to possess novel structure but also produces unique optical, electric and magnetic properties. Pyrazine-2,3-dicarboxylic acid (pzdcH2) has proved to be well suited for the construction of multidimensional frameworks, due to the presence of two adjacent carboxylate groups (O donor atoms) as substituents on the N-heterocyclic pyrazine ring (N donor atoms). A series of one-dimensional, two-dimensional and three-dimensional metal-organic coordination supramolecular complexes have been synthesized and characterized. Now, we report the crystal structure of the title compound (I), and the crystal structure is similar to the structures reported by Mao et al. (1996). In compound 1, the iron atom is hexacoordinate where the sphere about any iron atom includes the N1, N1A, O1, O1A, O3 and O3A atoms. The Fe atom lies on a crystallographic center of symmetry and that the ligand lies on a crystallographic twofold axis. Two coordinated water molecules are on the axis. The coordination distances for the Fe—O1 2.054 (1) Å are similar with the usual carboxyl oxygen to iron distance of 2.091 Å. The pzdc dianion ligands bridge Fe ions to form extended linear chains. In this structure, the pzdc dianion ligand coordinates to two metal centers via chelate interactions involving each nitrogen N(1) and oxygen O(1) from the adjacent carboxylate substituent (Fig. 1). As shown in Fig. 2, the chains are linked in a 3-D surpramolecular network by O—H···O hydrogen-bonding interactions.

Related literature top

For related literature, see: Kondo et al. (1999); Kitaura et al. (2002); Zheng et al. (2002); Mao et al. (1996); Castillo et al. (2003); Konar et al. (2004); Muranishi & Okabe (2003); Richard et al. (1973); Xiang et al. (2004); Zou et al. (1999).

Experimental top

The title compound was obtained by a diffusion method. In one arm of U-tube was placed (C6H2N2O4)Na2 (42 mg, 0.2 mmol) in water/ethanol (1:1; 10 ml) and in the other H12Cl2O14Fe (73 mg, 0.2 mmol) in water/ethanol (1:1; 10 ml). The red crystals were collected by filtration, washed with distilled water, followed by ethanol and dried under reduced pressure for 2 h.

Analysis found: C 24.39, H 3.41, N 9.26%; C6H10N2O8Fe requires: C 24.51, H 3.43, N 9.53%.

Refinement top

The H-atoms were included in the riding-model approximation with C—H = 0.93 - 0.96 Å and O—H = 0.82 Å, and with Uiso(H) = 1.2Ueq(C-aromatic).

Structure description top

Recently, the effective combination of coordination bond and hydrogen bond has been applied in the engineering study of inorganic-organic hybrid material and the construction of metal-organic coordination supramolecular complexes. The suitable organic ligand makes the complex not only to possess novel structure but also produces unique optical, electric and magnetic properties. Pyrazine-2,3-dicarboxylic acid (pzdcH2) has proved to be well suited for the construction of multidimensional frameworks, due to the presence of two adjacent carboxylate groups (O donor atoms) as substituents on the N-heterocyclic pyrazine ring (N donor atoms). A series of one-dimensional, two-dimensional and three-dimensional metal-organic coordination supramolecular complexes have been synthesized and characterized. Now, we report the crystal structure of the title compound (I), and the crystal structure is similar to the structures reported by Mao et al. (1996). In compound 1, the iron atom is hexacoordinate where the sphere about any iron atom includes the N1, N1A, O1, O1A, O3 and O3A atoms. The Fe atom lies on a crystallographic center of symmetry and that the ligand lies on a crystallographic twofold axis. Two coordinated water molecules are on the axis. The coordination distances for the Fe—O1 2.054 (1) Å are similar with the usual carboxyl oxygen to iron distance of 2.091 Å. The pzdc dianion ligands bridge Fe ions to form extended linear chains. In this structure, the pzdc dianion ligand coordinates to two metal centers via chelate interactions involving each nitrogen N(1) and oxygen O(1) from the adjacent carboxylate substituent (Fig. 1). As shown in Fig. 2, the chains are linked in a 3-D surpramolecular network by O—H···O hydrogen-bonding interactions.

For related literature, see: Kondo et al. (1999); Kitaura et al. (2002); Zheng et al. (2002); Mao et al. (1996); Castillo et al. (2003); Konar et al. (2004); Muranishi & Okabe (2003); Richard et al. (1973); Xiang et al. (2004); Zou et al. (1999).

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SMART (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL (Sheldrick, 1997b).

Figures top
[Figure 1] Fig. 1. The structure of (I) showing 30% probability displacement ellipsoids and the atom-numbering scheme. The H atoms are omitted for clarity.
[Figure 2] Fig. 2. three-dimensional supramolecular network of (I). O—H···O hydrogen bonds interactions shown.
catena-Poly[[[diaquairon(II)]-µ-pyrazine-2,3-dicarboxylato] dihydrate] top
Crystal data top
[Fe(C6H2N2O4)(H2O)2]·2H2OF(000) = 600
Mr = 294.01Dx = 1.869 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 3554 reflections
a = 12.5650 (2) Åθ = 3.3–28.2°
b = 7.5158 (1) ŵ = 1.48 mm1
c = 11.8314 (2) ÅT = 298 K
β = 110.759 (1)°Block, red
V = 1044.77 (3) Å30.23 × 0.20 × 0.18 mm
Z = 4
Data collection top
CCD area-detector
diffractometer
1291 independent reflections
Radiation source: fine-focus sealed tube1219 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.019
φ and ω scansθmax = 28.3°, θmin = 3.2°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1216
Tmin = 0.727, Tmax = 0.777k = 1010
5477 measured reflectionsl = 1515
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)] = 0.029H-atom parameters constrained
wR(F2) = 0.088 w = 1/[σ2(Fo2) + (0.0523P)2 + 1.9364P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
1291 reflectionsΔρmax = 0.59 e Å3
80 parametersΔρmin = 0.70 e Å3
0 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.028 (2)
Crystal data top
[Fe(C6H2N2O4)(H2O)2]·2H2OV = 1044.77 (3) Å3
Mr = 294.01Z = 4
Monoclinic, C2/cMo Kα radiation
a = 12.5650 (2) ŵ = 1.48 mm1
b = 7.5158 (1) ÅT = 298 K
c = 11.8314 (2) Å0.23 × 0.20 × 0.18 mm
β = 110.759 (1)°
Data collection top
CCD area-detector
diffractometer
1291 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1219 reflections with I > 2σ(I)
Tmin = 0.727, Tmax = 0.777Rint = 0.019
5477 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0290 restraints
wR(F2) = 0.088H-atom parameters constrained
S = 1.04Δρmax = 0.59 e Å3
1291 reflectionsΔρmin = 0.70 e Å3
80 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
Fe10.25000.25000.50000.01865 (18)
C10.08321 (16)0.0176 (3)0.38935 (17)0.0225 (4)
C20.04250 (15)0.1436 (3)0.30732 (16)0.0202 (4)
C30.04814 (18)0.4486 (3)0.30161 (19)0.0289 (5)
H30.08400.55570.33200.035*
N10.09020 (14)0.2975 (2)0.35810 (15)0.0228 (3)
O10.18127 (13)0.0012 (2)0.47077 (14)0.0283 (3)
O20.01979 (14)0.1458 (2)0.37732 (17)0.0378 (4)
O30.32048 (15)0.2010 (3)0.36718 (16)0.0387 (4)
H3A0.33360.09410.35250.046*
H3B0.36190.28050.35240.046*
O40.1817 (2)0.2742 (3)0.14299 (19)0.0509 (6)
H4A0.15310.18320.10040.061*
H4B0.22260.34060.11680.061*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Fe10.0141 (2)0.0209 (3)0.0166 (2)0.00144 (12)0.00016 (15)0.00229 (12)
C10.0209 (8)0.0219 (9)0.0224 (8)0.0007 (7)0.0047 (7)0.0014 (7)
C20.0158 (8)0.0194 (9)0.0222 (9)0.0005 (6)0.0030 (7)0.0004 (7)
C30.0279 (10)0.0193 (9)0.0318 (11)0.0031 (8)0.0010 (9)0.0023 (8)
N10.0181 (7)0.0223 (8)0.0226 (8)0.0007 (6)0.0005 (5)0.0013 (6)
O10.0244 (7)0.0240 (6)0.0276 (7)0.0012 (5)0.0018 (6)0.0040 (5)
O20.0301 (8)0.0273 (8)0.0484 (10)0.0073 (6)0.0047 (7)0.0081 (7)
O30.0317 (9)0.0544 (11)0.0337 (9)0.0109 (8)0.0160 (7)0.0108 (8)
O40.0651 (14)0.0589 (13)0.0310 (9)0.0257 (10)0.0200 (10)0.0104 (8)
Geometric parameters (Å, º) top
Fe1—O1i2.0539 (15)C2—N11.343 (3)
Fe1—O12.0539 (15)C2—C2ii1.398 (3)
Fe1—O32.0919 (17)C3—N11.329 (3)
Fe1—O3i2.0919 (17)C3—C3ii1.381 (4)
Fe1—N1i2.1420 (17)C3—H30.9300
Fe1—N12.1420 (17)O3—H3A0.8500
C1—O21.226 (3)O3—H3B0.8500
C1—O11.273 (2)O4—H4A0.8500
C1—C21.523 (3)O4—H4B0.8501
O1i—Fe1—O1180.0O2—C1—C2119.56 (17)
O1i—Fe1—O391.35 (7)O1—C1—C2114.93 (16)
O1—Fe1—O388.65 (7)N1—C2—C2ii120.03 (11)
O1i—Fe1—O3i88.65 (7)N1—C2—C1113.86 (16)
O1—Fe1—O3i91.35 (7)C2ii—C2—C1125.94 (10)
O3—Fe1—O3i180.000 (1)N1—C3—C3ii120.82 (11)
O1i—Fe1—N1i78.46 (6)N1—C3—H3119.6
O1—Fe1—N1i101.54 (6)C3ii—C3—H3119.6
O3—Fe1—N1i91.76 (7)C3—N1—C2118.46 (17)
O3i—Fe1—N1i88.24 (7)C3—N1—Fe1129.20 (14)
O1i—Fe1—N1101.54 (6)C2—N1—Fe1110.65 (13)
O1—Fe1—N178.46 (6)C1—O1—Fe1116.94 (13)
O3—Fe1—N188.24 (7)Fe1—O3—H3A118.9
O3i—Fe1—N191.76 (7)Fe1—O3—H3B118.9
N1i—Fe1—N1180.0H3A—O3—H3B116.4
O2—C1—O1125.39 (19)H4A—O4—H4B116.0
Symmetry codes: (i) x+1/2, y+1/2, z+1; (ii) x, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H4A···O1iii0.852.172.890 (3)142
O4—H4A···O2iii0.852.593.227 (3)133
O4—H4B···O1iv0.852.203.045 (3)174
O3—H3A···O4v0.852.413.210 (3)156
O3—H3B···O2vi0.851.982.720 (2)145
C3—H3···O2vii0.932.513.232 (3)135
Symmetry codes: (iii) x, y, z1/2; (iv) x+1/2, y+1/2, z+1/2; (v) x+1/2, y1/2, z+1/2; (vi) x+1/2, y+1/2, z; (vii) x, y+1, z.

Experimental details

Crystal data
Chemical formula[Fe(C6H2N2O4)(H2O)2]·2H2O
Mr294.01
Crystal system, space groupMonoclinic, C2/c
Temperature (K)298
a, b, c (Å)12.5650 (2), 7.5158 (1), 11.8314 (2)
β (°) 110.759 (1)
V3)1044.77 (3)
Z4
Radiation typeMo Kα
µ (mm1)1.48
Crystal size (mm)0.23 × 0.20 × 0.18
Data collection
DiffractometerCCD area-detector
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.727, 0.777
No. of measured, independent and
observed [I > 2σ(I)] reflections
5477, 1291, 1219
Rint0.019
(sin θ/λ)max1)0.666
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.029, 0.088, 1.04
No. of reflections1291
No. of parameters80
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.59, 0.70

Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 1997a), SHELXL97 (Sheldrick, 1997a), SHELXTL (Sheldrick, 1997b).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H4A···O1i0.852.172.890 (3)141.7
O4—H4A···O2i0.852.593.227 (3)132.5
O4—H4B···O1ii0.852.203.045 (3)173.6
O3—H3A···O4iii0.852.413.210 (3)156.1
O3—H3B···O2iv0.851.982.720 (2)145.2
C3—H3···O2v0.932.513.232 (3)135.2
Symmetry codes: (i) x, y, z1/2; (ii) x+1/2, y+1/2, z+1/2; (iii) x+1/2, y1/2, z+1/2; (iv) x+1/2, y+1/2, z; (v) x, y+1, z.
 

Acknowledgements

The authors thank the Natural Science Foundation of Henan Province (grant No. 0511020300) for financial support.

References

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