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rz5089 scheme

Acta Cryst. (2013). E69, m625    [ doi:10.1107/S1600536813029449 ]

Bis([mu]-hydroxido-[kappa]2O:O)bis[bis(5-car­boxy­pyridine-2-carboxyl­ato-[kappa]2N,O2)iron(III)] dihydrate

W. Cao

Abstract top

The complete binuclear complex in [Fe2(C7H4NO4)4(OH)2]·2H2O, is generated by the application twofold symmetry. The FeIII atom is coordinated by the O atoms of two bridging hydroxyl groups and by two N and two O atoms from two pyridine-2,5-di­carboxyl­ato ligands, forming a distorted octa­hedral geometry. The Fe...Fe separation within the dinuclear complex is 3.0657 (4) Å. In the crystal, O-H...O and C-H...O hydrogen-bonding inter­actions connect the mol­ecules into a three-dimensional supra­molecular network.

Comment top

In the past few decades, pyridine-2,5-dicarboxylic acid (H2pydc) has attracted considerable attention for its ability to coordinate to different metal centres. It can display different kinds of coordination modes, and the relative position of the coordinative moieties is adequate to form supramolecular structures of varied structural features (Zhang et al., 2006; Liang et al., 2000; Wibowo et al., 2011; Zhang et al., 2005). A number of compounds based on pyridine-2,5-dicarboxylic acid and transition metals have been reported, few of them containing Fe ions (Shi et al., 2011; Xu et al., 2004; Gao et al., 2005). Herein, the synthesis and crystal structure of a novel binuclear iron(III) derivative is reported.

As shown in Fig. 1, the metal is coordinated by two O atoms (O1, O5) and two N atoms (N3, N5) from two Hpydc- ligands and two µ2-OH groups (O9, O9A) to form a slightly distorted octahedral geometry. Two iron metals related by a two-fold axis are bridged by the OH groups to form a binuclear complex molecule. The mean Fe—O and Fe—N distances are 1.971 (9) Å and 2.114 (2) Å, respectively. In the crystal, the title compound features two kinds of hydrogen interactions (O—H···O and C—H···O; Table 1), which connect the binuclear units into a three-dimensional supramolecular network (Fig. 2).

Related literature top

For background to the coordination modes of the pyridine-2,5-dicarboxylate ligand, see: Zhang et al. (2005, 2006); Liang et al. (2000); Wibowo et al. (2011). For iron complexes of the pyridine-2,5-dicarboxylate ligand, see: Shi et al. (2011); Xu et al. (2004); Gao et al. (2005).

Experimental top

A mixture of pyridine-2,5-dicarboxylic acid (0.0335 g, 0.2 mmol), Sr(OH)2·8H2O (0.0267 g, 0.1 mmol), Fe(NO3)3·9H2O (0.0404 g, 0.1 mmol), imidazole (0.0235 g, 0.35 mmol), and H2O (3 ml, v/v = 2:1) was sealed in a Pyrex-tube (8 ml) and heated at 120°C for 2 days. The tube was then cooled to room temperature, generating bright-green rod crystals. Yield: 0.0237 g (56%, based on Fe). Elemental analysis calc. for C28H22Fe2N4O20: C, 39.74; H, 2.62; N, 6.62%. Found: C, 39.66; H, 2.65; N, 6.69%.

Refinement top

Water and hydroxy H atoms were located in a difference Fourier map and refined as riding, with O—H = 0.85-0.88 Å and Uiso(H) = 1.5 Ueq(O). All other H atoms were positioned geometrically and refined as riding with C—H = 0.93 Å and Uiso(H) = 1.2 Ueq (C).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing 30% probability displacement ellipsoids. Symmetry code: (A) -x + 2, y,-z + 1/2.
[Figure 2] Fig. 2. Crystal packing of the title compound viewed down the a axis. Displacement ellipsoids are drawn at the 30% probability level. Hydrogen bonds are shown as dashed lines.
Bis(µ-hydroxido-κ2O:O)bis[bis(5-carboxypyridine-2-carboxylato-κ2N,O2)iron(III)] dihydrate top
Crystal data top
[Fe2(C7H4NO4)4(OH)2]·2H2OF(000) = 860
Mr = 846.20Dx = 1.749 Mg m3
Monoclinic, P2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ycCell parameters from 3376 reflections
a = 7.6130 (7) Åθ = 2.8–27.8°
b = 14.2716 (14) ŵ = 1.00 mm1
c = 16.2594 (13) ÅT = 298 K
β = 114.556 (4)°Rod, green
V = 1606.8 (3) Å30.28 × 0.25 × 0.20 mm
Z = 2
Data collection top
Bruker APEXII CCD
diffractometer
3972 independent reflections
Radiation source: fine-focus sealed tube3224 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
φ and ω scansθmax = 28.3°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 109
Tmin = 0.767, Tmax = 0.825k = 1915
11029 measured reflectionsl = 2121
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)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.096H-atom parameters constrained
S = 1.01 w = 1/[σ2(Fo2) + (0.0446P)2 + 0.9967P]
where P = (Fo2 + 2Fc2)/3
3972 reflections(Δ/σ)max < 0.001
244 parametersΔρmax = 0.37 e Å3
0 restraintsΔρmin = 0.47 e Å3
Crystal data top
[Fe2(C7H4NO4)4(OH)2]·2H2OV = 1606.8 (3) Å3
Mr = 846.20Z = 2
Monoclinic, P2/cMo Kα radiation
a = 7.6130 (7) ŵ = 1.00 mm1
b = 14.2716 (14) ÅT = 298 K
c = 16.2594 (13) Å0.28 × 0.25 × 0.20 mm
β = 114.556 (4)°
Data collection top
Bruker APEXII CCD
diffractometer
3972 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
3224 reflections with I > 2σ(I)
Tmin = 0.767, Tmax = 0.825Rint = 0.026
11029 measured reflectionsθmax = 28.3°
Refinement top
R[F2 > 2σ(F2)] = 0.035H-atom parameters constrained
wR(F2) = 0.096Δρmax = 0.37 e Å3
S = 1.01Δρmin = 0.47 e Å3
3972 reflectionsAbsolute structure: ?
244 parametersAbsolute structure parameter: ?
0 restraintsRogers parameter: ?
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
Fe10.80977 (4)0.202541 (19)0.164770 (19)0.02479 (10)
O10.7658 (2)0.21500 (10)0.03507 (10)0.0320 (3)
C10.7583 (3)0.37700 (14)0.06158 (13)0.0276 (4)
O20.7390 (3)0.30988 (11)0.07630 (11)0.0422 (4)
C20.7485 (3)0.46928 (15)0.03644 (15)0.0364 (5)
H20.74590.48590.01940.044*
N30.7556 (2)0.05572 (11)0.14087 (12)0.0270 (4)
C30.7427 (4)0.53720 (16)0.09617 (16)0.0384 (5)
H30.73560.60030.08080.046*
O30.7248 (4)0.66606 (13)0.22363 (14)0.0732 (7)
O40.7493 (4)0.55104 (13)0.31845 (12)0.0619 (6)
H40.74320.59810.34920.093*
C40.7476 (3)0.51062 (14)0.17838 (14)0.0311 (4)
O50.5359 (2)0.19337 (10)0.14846 (11)0.0346 (3)
N50.7678 (2)0.35085 (12)0.14291 (11)0.0264 (3)
C50.7609 (3)0.41600 (14)0.20041 (14)0.0302 (4)
H50.76510.39780.25610.036*
O60.2935 (2)0.09752 (13)0.13321 (15)0.0517 (5)
C60.7553 (3)0.29598 (14)0.00125 (14)0.0281 (4)
O70.8655 (3)0.25246 (13)0.07024 (15)0.0579 (5)
C70.7401 (4)0.58513 (16)0.24209 (16)0.0378 (5)
O81.1183 (3)0.15856 (12)0.13517 (14)0.0515 (5)
H81.17830.20460.13090.077*
C80.5788 (3)0.03170 (15)0.13346 (15)0.0308 (4)
O90.9102 (2)0.20283 (10)0.29588 (10)0.0295 (3)
H9A0.84740.18070.32460.044*
C90.5143 (4)0.05918 (16)0.12100 (19)0.0442 (6)
H90.39210.07380.11720.053*
C100.6332 (3)0.12806 (16)0.11428 (18)0.0435 (6)
H100.59310.19030.10650.052*
O100.2618 (4)0.34823 (19)0.09961 (18)0.0971 (9)
H10A0.26830.29040.11760.146*
H10B0.19970.32790.04400.146*
C110.8133 (3)0.10417 (15)0.11911 (15)0.0322 (4)
C120.8722 (3)0.01115 (14)0.13374 (14)0.0288 (4)
H120.99450.00500.13870.035*
C130.4555 (3)0.11238 (16)0.13878 (15)0.0333 (5)
C140.9348 (4)0.17947 (15)0.10565 (17)0.0376 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Fe10.03269 (17)0.01681 (15)0.02696 (16)0.00018 (11)0.01447 (12)0.00000 (11)
O10.0489 (9)0.0203 (7)0.0281 (7)0.0003 (6)0.0173 (7)0.0018 (6)
C10.0343 (10)0.0215 (9)0.0284 (10)0.0000 (8)0.0144 (8)0.0006 (8)
O20.0745 (12)0.0278 (8)0.0328 (8)0.0048 (7)0.0309 (8)0.0031 (6)
C20.0549 (14)0.0255 (11)0.0331 (11)0.0019 (9)0.0224 (10)0.0029 (9)
N30.0325 (9)0.0200 (8)0.0313 (8)0.0020 (7)0.0162 (7)0.0021 (7)
C30.0579 (14)0.0200 (10)0.0414 (12)0.0024 (9)0.0247 (11)0.0012 (9)
O30.150 (2)0.0244 (9)0.0644 (13)0.0098 (11)0.0631 (15)0.0020 (9)
O40.1225 (18)0.0296 (10)0.0442 (10)0.0052 (10)0.0452 (12)0.0055 (8)
C40.0381 (11)0.0210 (10)0.0339 (11)0.0019 (8)0.0146 (9)0.0026 (8)
O50.0332 (8)0.0254 (8)0.0474 (9)0.0016 (6)0.0189 (7)0.0015 (6)
N50.0342 (9)0.0195 (8)0.0274 (8)0.0024 (7)0.0149 (7)0.0011 (6)
C50.0399 (11)0.0241 (10)0.0285 (10)0.0023 (8)0.0163 (9)0.0009 (8)
O60.0397 (9)0.0413 (10)0.0850 (14)0.0057 (8)0.0370 (9)0.0127 (10)
C60.0339 (10)0.0232 (10)0.0295 (10)0.0004 (8)0.0156 (8)0.0005 (8)
O70.0709 (13)0.0267 (9)0.0846 (14)0.0100 (8)0.0409 (11)0.0218 (9)
C70.0531 (14)0.0255 (11)0.0384 (12)0.0043 (9)0.0226 (11)0.0029 (9)
O80.0502 (10)0.0285 (9)0.0842 (14)0.0002 (8)0.0364 (10)0.0146 (9)
C80.0354 (11)0.0247 (10)0.0371 (11)0.0025 (8)0.0197 (9)0.0021 (9)
O90.0327 (7)0.0322 (8)0.0277 (7)0.0008 (6)0.0168 (6)0.0009 (6)
C90.0399 (13)0.0293 (12)0.0702 (17)0.0096 (10)0.0295 (12)0.0064 (11)
C100.0444 (13)0.0235 (11)0.0650 (16)0.0095 (9)0.0250 (12)0.0078 (11)
O100.141 (3)0.0694 (18)0.0912 (19)0.0195 (17)0.0580 (18)0.0053 (15)
C110.0399 (11)0.0216 (10)0.0360 (11)0.0012 (8)0.0167 (9)0.0026 (9)
C120.0337 (10)0.0214 (10)0.0342 (10)0.0000 (8)0.0170 (9)0.0007 (8)
C130.0341 (11)0.0315 (11)0.0383 (11)0.0001 (9)0.0190 (9)0.0029 (9)
C140.0506 (14)0.0219 (10)0.0468 (13)0.0033 (9)0.0268 (11)0.0038 (9)
Geometric parameters (Å, º) top
Fe1—O91.9427 (15)C4—C71.502 (3)
Fe1—O9i1.9543 (15)O5—C131.287 (3)
Fe1—O51.9937 (15)N5—C51.335 (3)
Fe1—O12.0011 (15)C5—H50.9300
Fe1—N32.1397 (17)O6—C131.217 (3)
Fe1—N52.1480 (17)O7—C141.201 (3)
O1—C61.268 (2)O8—C141.309 (3)
C1—N51.347 (3)O8—H80.8200
C1—C21.372 (3)C8—C91.372 (3)
C1—C61.510 (3)C8—C131.511 (3)
O2—C61.231 (2)O9—Fe1i1.9543 (15)
C2—C31.386 (3)O9—H9A0.8554
C2—H20.9300C9—C101.371 (3)
N3—C121.340 (3)C9—H90.9300
N3—C81.345 (3)C10—C111.383 (3)
C3—C41.375 (3)C10—H100.9300
C3—H30.9300O10—H10A0.8695
O3—C71.187 (3)O10—H10B0.8773
O4—C71.308 (3)C11—C121.390 (3)
O4—H40.8500C11—C141.492 (3)
C4—C51.390 (3)C12—H120.9300
O9—Fe1—O9i76.25 (7)N5—C5—C4121.07 (19)
O9—Fe1—O593.39 (6)N5—C5—H5119.5
O9i—Fe1—O5169.02 (6)C4—C5—H5119.5
O9—Fe1—O1166.74 (6)O2—C6—O1123.53 (19)
O9i—Fe1—O191.53 (6)O2—C6—C1120.67 (18)
O5—Fe1—O199.10 (7)O1—C6—C1115.78 (18)
O9—Fe1—N399.19 (6)O3—C7—O4124.3 (2)
O9i—Fe1—N399.39 (6)O3—C7—C4122.8 (2)
O5—Fe1—N378.44 (6)O4—C7—C4112.89 (19)
O1—Fe1—N387.73 (6)C14—O8—H8109.5
O9—Fe1—N598.23 (6)N3—C8—C9122.5 (2)
O9i—Fe1—N596.84 (6)N3—C8—C13115.04 (18)
O5—Fe1—N588.13 (6)C9—C8—C13122.4 (2)
O1—Fe1—N577.87 (6)Fe1—O9—Fe1i103.75 (7)
N3—Fe1—N5158.55 (7)Fe1—O9—H9A122.9
C6—O1—Fe1119.39 (13)Fe1i—O9—H9A127.0
N5—C1—C2122.20 (19)C10—C9—C8118.8 (2)
N5—C1—C6113.94 (17)C10—C9—H9120.6
C2—C1—C6123.85 (19)C8—C9—H9120.6
C1—C2—C3118.4 (2)C9—C10—C11119.4 (2)
C1—C2—H2120.8C9—C10—H10120.3
C3—C2—H2120.8C11—C10—H10120.3
C12—N3—C8118.98 (17)H10A—O10—H10B87.9
C12—N3—Fe1128.94 (14)C10—C11—C12119.1 (2)
C8—N3—Fe1112.08 (13)C10—C11—C14118.3 (2)
C4—C3—C2119.5 (2)C12—C11—C14122.5 (2)
C4—C3—H3120.3N3—C12—C11121.13 (19)
C2—C3—H3120.3N3—C12—H12119.4
C7—O4—H4105.7C11—C12—H12119.4
C3—C4—C5119.2 (2)O6—C13—O5125.6 (2)
C3—C4—C7118.80 (19)O6—C13—C8119.8 (2)
C5—C4—C7122.0 (2)O5—C13—C8114.59 (18)
C13—O5—Fe1119.57 (13)O7—C14—O8124.2 (2)
C5—N5—C1119.53 (17)O7—C14—C11121.3 (2)
C5—N5—Fe1128.09 (14)O8—C14—C11114.47 (19)
C1—N5—Fe1112.28 (13)
O9—Fe1—O1—C666.9 (3)C3—C4—C5—N50.4 (3)
O9i—Fe1—O1—C689.41 (16)C7—C4—C5—N5179.9 (2)
O5—Fe1—O1—C693.34 (16)Fe1—O1—C6—O2175.93 (17)
N3—Fe1—O1—C6171.25 (16)Fe1—O1—C6—C15.7 (2)
N5—Fe1—O1—C67.26 (16)N5—C1—C6—O2177.1 (2)
N5—C1—C2—C31.9 (3)C2—C1—C6—O21.7 (3)
C6—C1—C2—C3176.8 (2)N5—C1—C6—O11.3 (3)
O9—Fe1—N3—C1291.72 (18)C2—C1—C6—O1179.9 (2)
O9i—Fe1—N3—C1214.28 (18)C3—C4—C7—O32.1 (4)
O5—Fe1—N3—C12176.66 (19)C5—C4—C7—O3178.5 (3)
O1—Fe1—N3—C1276.90 (18)C3—C4—C7—O4178.8 (2)
N5—Fe1—N3—C12124.4 (2)C5—C4—C7—O40.7 (3)
O9—Fe1—N3—C887.60 (15)C12—N3—C8—C91.6 (3)
O9i—Fe1—N3—C8165.05 (14)Fe1—N3—C8—C9177.8 (2)
O5—Fe1—N3—C84.01 (14)C12—N3—C8—C13177.72 (18)
O1—Fe1—N3—C8103.78 (15)Fe1—N3—C8—C132.9 (2)
N5—Fe1—N3—C856.3 (2)O9i—Fe1—O9—Fe1i0.25 (9)
C1—C2—C3—C40.2 (4)O5—Fe1—O9—Fe1i176.08 (6)
C2—C3—C4—C50.9 (4)O1—Fe1—O9—Fe1i23.5 (3)
C2—C3—C4—C7179.6 (2)N3—Fe1—O9—Fe1i97.25 (7)
O9—Fe1—O5—C1393.78 (17)N5—Fe1—O9—Fe1i95.32 (7)
O9i—Fe1—O5—C1374.7 (4)N3—C8—C9—C101.1 (4)
O1—Fe1—O5—C1390.68 (17)C13—C8—C9—C10178.1 (2)
N3—Fe1—O5—C134.91 (16)C8—C9—C10—C110.8 (4)
N5—Fe1—O5—C13168.08 (17)C9—C10—C11—C122.2 (4)
C2—C1—N5—C52.4 (3)C9—C10—C11—C14176.1 (2)
C6—C1—N5—C5176.44 (18)C8—N3—C12—C110.1 (3)
C2—C1—N5—Fe1174.31 (18)Fe1—N3—C12—C11179.16 (15)
C6—C1—N5—Fe16.9 (2)C10—C11—C12—N31.7 (3)
O9—Fe1—N5—C516.69 (18)C14—C11—C12—N3176.5 (2)
O9i—Fe1—N5—C593.71 (18)Fe1—O5—C13—O6175.8 (2)
O5—Fe1—N5—C576.46 (18)Fe1—O5—C13—C84.7 (3)
O1—Fe1—N5—C5176.19 (19)N3—C8—C13—O6179.6 (2)
N3—Fe1—N5—C5127.3 (2)C9—C8—C13—O61.1 (4)
O9—Fe1—N5—C1159.65 (14)N3—C8—C13—O50.9 (3)
O9i—Fe1—N5—C182.63 (14)C9—C8—C13—O5178.4 (2)
O5—Fe1—N5—C1107.19 (14)C10—C11—C14—O718.1 (4)
O1—Fe1—N5—C17.47 (14)C12—C11—C14—O7160.1 (2)
N3—Fe1—N5—C156.3 (2)C10—C11—C14—O8162.0 (2)
C1—N5—C5—C41.2 (3)C12—C11—C14—O819.8 (3)
Fe1—N5—C5—C4174.93 (15)
Symmetry code: (i) x+2, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O8—H8···O2ii0.821.982.761 (2)160
O4—H4···O2iii0.851.802.643 (2)175
O9—H9A···O6iv0.861.912.735 (2)162
O10—H10A···O50.872.342.914 (3)124
O10—H10B···O7v0.882.022.865 (3)161
C3—H3···O7vi0.932.363.223 (3)155
C5—H5···O10iv0.932.543.465 (3)174
C9—H9···O8vii0.932.533.425 (3)162
Symmetry codes: (ii) x+2, y, z; (iii) x, y+1, z+1/2; (iv) x+1, y, z+1/2; (v) x+1, y, z; (vi) x, y+1, z; (vii) x1, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O8—H8···O2i0.821.982.761 (2)160.1
O4—H4···O2ii0.851.802.643 (2)174.5
O9—H9A···O6iii0.861.912.735 (2)162.0
O10—H10A···O50.872.342.914 (3)123.8
O10—H10B···O7iv0.882.022.865 (3)160.7
C3—H3···O7v0.932.363.223 (3)154.5
C5—H5···O10iii0.932.543.465 (3)174.0
C9—H9···O8vi0.932.533.425 (3)161.6
Symmetry codes: (i) x+2, y, z; (ii) x, y+1, z+1/2; (iii) x+1, y, z+1/2; (iv) x+1, y, z; (v) x, y+1, z; (vi) x1, y, z.
Acknowledgements top

This work was supportedfinancially by the HuangHe Hydropower Development Co. Ltd, Qinghai.

references
References top

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