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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 8| August 2012| Pages m1093-m1094
https://doi.org/10.1107/S1600536812031753

Triclinic modification of di­aqua­bis­­(5-carb­­oxy-1H-imidazole-4-carboxyl­ato-κ2N3,O4)iron(II)

Eriko Ohshima,a Kazuki Yoshida,a Kazumasa Sugiyamab* and Hidehiro Uekusac

aDepartment of Chemical Engineering, Ichinoseki National College of Technology, Takanashi, Hagisyo, Ichinoseki 021-8511, Japan, bInstitute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan, and cDepartment of Chemistry and Materials Science, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8551, Japan
*Correspondence e-mail: kazumasa@imr.tohoku.ac.jp

(Received 12 June 2012; accepted 11 July 2012; online 21 July 2012)

The title compound, [Fe(C5H3N2O4)2(H2O)2], is a triclinic modification of a monoclinic form recently reported by Du et al. [Acta Cryst. (2011)[Du, C.-J., Song, X.-H., Wang, L.-S. & Du, C.-L. (2011). Acta Cryst. E67, m997.], E67, m997]. The FeII ion lies at an inversion center and is coordinated by two N and two O atoms from two 5-carb­oxy-1H-imidazole-4-carboxyl­ate ligands in trans positions, together with two water mol­ecules, completing a slightly distorted octahedral coordination. Inter­molecular N—H⋯O hydrogen bonding between the N—H group of the imidazole ring and the deprotonated carboxyl­ate group builds a chain of 5-carb­oxy-1H-imidazole-4-carboxyl­ate anions along the [101] direction. The water molecules form intermolecular hydrogen bonds to O—C and O=C sites of the carboxylate group in adjacent layers.

Related literature

For the structural diversity of the coordination architecture of the metal complexes of 4,5-imidazole­dicarb­oxy­lic acid, see Shimizu et al. (2004[Shimizu, E., Kondo, M., Ruwa, Y., Sarker, R. P., Miyazawa, M., Ueno, M., Naito, T., Maeda, K. & Uchida, F. (2004). Inorg. Chem. Commun. 7, 1191-1194.]); Fang & Zhang (2006[Fang, R.-Q. & Zhang, X.-M. (2006). Inorg. Chem. 45, 4801-4810.]). For the isotypic Co analog, see: Li et al. (2011[Li, J.-X., Du, Z.-X., Wang, L.-Z. & Huang, W.-P. (2011). Inorg. Chim. Acta, 376, 479-485.]). For the coexisting phase, see Yakubovich et al. (1995[Yakubovich, O. V., Karinova, O. V., Mel'nikov, O. K. & Urusov, V. S. (1995). Dokl. Akad. Nauk, 342, 40-44.]). For the monoclinic form, see: Du et al. (2011[Du, C.-J., Song, X.-H., Wang, L.-S. & Du, C.-L. (2011). Acta Cryst. E67, m997.]).

[Scheme 1]

Experimental

Crystal data

  • [Fe(C5H3N2O4)2(H2O)2]

  • Mr = 402.08

  • Triclinic, [P \overline 1]

  • a = 4.9290 (5) Å

  • b = 6.4258 (6) Å

  • c = 12.2812 (10) Å

  • α = 78.161 (3)°

  • β = 85.175 (3)°

  • γ = 72.776 (4)°

  • V = 363.52 (6) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 1.10 mm−1

  • T = 298 K

  • 0.15 × 0.13 × 0.10 mm
Data collection

  • Rigaku R-AXIS RAPID diffractometer

  • Absorption correction: empirical (using intensity measurements) (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.852, Tmax = 0.898

  • 3655 measured reflections

  • 1668 independent reflections

  • 1066 reflections with I > 2σ(I)

  • Rint = 0.050
Refinement

  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.075

  • S = 0.92

  • 1668 reflections

  • 122 parameters

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

  • Δρmax = 0.30 e Å−3

  • Δρmin = −0.34 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O5—H1W⋯O3i 0.86 (3) 1.86 (3) 2.705 (3) 165 (3)
O5—H2W⋯O4ii 0.79 (3) 1.95 (3) 2.702 (3) 158 (3)
N2—H2A⋯O1iii 0.86 1.95 2.767 (3) 157
O2—H2⋯O3 0.82 1.85 2.665 (3) 174
Symmetry codes: (i) -x, -y-1, -z; (ii) x+1, y, z; (iii) -x+1, -y, -z-1.

Data collection: RAPID-AUTO (Rigaku, 1998[Rigaku (1998). RAPID-AUTO. Rigaku Corporation, Tokyo, Japan.]); cell refinement: RAPID-AUTO; data reduction: RAPID-AUTO; program(s) used to solve structure: SIR97 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); 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: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536812031753/fj2571sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812031753/fj2571Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536812031753/fj2571Isup6.mol

checkCIF report


Comment top

A number of studies on transition metal complexes with carboxylate ligands are reported in the literature. Recently, imidazole dicarboxylate has been recognized as an efficient building block, since it shows two different coordination modes to bridge or chelate metals through the carboxyl oxygen atoms and heterocyclic nitrogen donor. The crystal of diaquabis(5-carboxy-1H-imidazole-4-carboxylato-κ2N3,\ O)iron(II) is isostructural with Co analog 4,5-dicarboxyimidazole complexes (Li et al., 2011). Iron(II) ion lies at the inversion center that is coordinated by two 1H-imidazole-4,5-dicarboxylate monoanionic ligands at the trans positions and two water molecules in a distorted octahedral geometry. A previous report described a monoclinic metal complex with a similar chemical composition (Du et al., 2011). This structural diversity is attributed to the different types of coordination architectures of hydrogen bonding between molecules. The intermolecular hydrogen bonding between the N—H site of an imidazole ring and C═O site of a deprotonated carboxylate in the title compound builds a unique chain of 5-carboxy-1H- imidazole-4-carboxylate anion. The chain structures are further linked into a three-dimensional supermolecular framework through O—H···O hydrogen bonding interactions. The average distance of Fe—O agrees well with that of the monoclinic phase. Nevertheless, the average distance of Fe—N (2.165 Å) is longer than that in the monoclinic analog (2.147 Å).

Related literature top

For the structural diversity of the coordination architecture of the metal complexes of 4,5-imidazoledicarboxylic acid, see Shimizu et al. (2004); Fang & Zhang, (2006). For the isotypic Co analog, see Li et al. (2011). For the coexisting phase, see Yakubovich et al. (1995). For the monoclinic form literature, see: Du et al. (2011).

Experimental top

A mixture of FeSO4. 7H2O (13.33 mmol), 4,5-imidazoledicarboxamide (22.21 mmol), 85.0% H3PO4 (8.89 mmol), and H2O (8 ml) was placed in a 30 ml Teflon beaker. It was sealed in a stainless-steel reactor, heated to 453 K for 96 h under autogenous pressure, and then, slowly cooled to room temperature. Pale-yellow block crystals of the title complex were isolated, washed with distilled water, and dried in air. It may be added that NH4FePO4.H2O: see Yakubovich et al. (1995), Pale-green plate crystals were also crystallized in the present synthetic condition. This supports the hydrolysis of the 4,5-imidazoledicarboxamide during the synthesis.

Refinement top

H atoms attached to C and N atoms were placed at calculated positions (C—H = 0.93 Å, N—H = 0.86 Å) and refined as riding atoms with Uiso(H) = 1.2Ueq(C, N). The carboxy H was located at the idealized position (O—H = 0.82 Å) and refined as a riding atom with Uiso(H) = 1.5 Ueq(O). On the other hand, H atoms of water molecules were located in a difference map, and their positions were subsequently refined with Uiso(H) = 1.5Ueq(O).

Structure description top

A number of studies on transition metal complexes with carboxylate ligands are reported in the literature. Recently, imidazole dicarboxylate has been recognized as an efficient building block, since it shows two different coordination modes to bridge or chelate metals through the carboxyl oxygen atoms and heterocyclic nitrogen donor. The crystal of diaquabis(5-carboxy-1H-imidazole-4-carboxylato-κ2N3,\ O)iron(II) is isostructural with Co analog 4,5-dicarboxyimidazole complexes (Li et al., 2011). Iron(II) ion lies at the inversion center that is coordinated by two 1H-imidazole-4,5-dicarboxylate monoanionic ligands at the trans positions and two water molecules in a distorted octahedral geometry. A previous report described a monoclinic metal complex with a similar chemical composition (Du et al., 2011). This structural diversity is attributed to the different types of coordination architectures of hydrogen bonding between molecules. The intermolecular hydrogen bonding between the N—H site of an imidazole ring and C═O site of a deprotonated carboxylate in the title compound builds a unique chain of 5-carboxy-1H- imidazole-4-carboxylate anion. The chain structures are further linked into a three-dimensional supermolecular framework through O—H···O hydrogen bonding interactions. The average distance of Fe—O agrees well with that of the monoclinic phase. Nevertheless, the average distance of Fe—N (2.165 Å) is longer than that in the monoclinic analog (2.147 Å).

For the structural diversity of the coordination architecture of the metal complexes of 4,5-imidazoledicarboxylic acid, see Shimizu et al. (2004); Fang & Zhang, (2006). For the isotypic Co analog, see Li et al. (2011). For the coexisting phase, see Yakubovich et al. (1995). For the monoclinic form literature, see: Du et al. (2011).

Computing details top

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: RAPID-AUTO (Rigaku, 1998); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure with displacement ellipsoids drawn at the 50% probability level.
Diaquabis(5-carboxy-1H-imidazole-4- carboxylato-κ2N3,O4)iron(II) top
Crystal data top
[Fe(C5H3N2O4)2(H2O)2]Z = 1
Mr = 402.08F(000) = 204
Triclinic, P1Dx = 1.837 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71069 Å
a = 4.9290 (5) ÅCell parameters from 3918 reflections
b = 6.4258 (6) Åθ = 3.4–30.5°
c = 12.2812 (10) ŵ = 1.10 mm−1
α = 78.161 (3)°T = 298 K
β = 85.175 (3)°Block, yellow
γ = 72.776 (4)°0.15 × 0.13 × 0.10 mm
V = 363.52 (6) Å3
Data collection top
Rigaku R-AXIS RAPID
diffractometer		1668 independent reflections
Radiation source: fine-focus sealed tube1066 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.050
Detector resolution: 100 pixels mm-1θmax = 27.5°, θmin = 3.4°
ω scansh = −6→6
Absorption correction: empirical (using intensity measurements)
(ABSCOR; Higashi, 1995)		k = −8→8
Tmin = 0.852, Tmax = 0.898l = −15→15
3655 measured reflections
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)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.075H atoms treated by a mixture of independent and constrained refinement
S = 0.92 w = 1/[σ2(Fo2) + (0.0339P)2]
where P = (Fo2 + 2Fc2)/3
1668 reflections(Δ/σ)max < 0.001
122 parametersΔρmax = 0.30 e Å−3
0 restraintsΔρmin = −0.34 e Å−3
Crystal data top
[Fe(C5H3N2O4)2(H2O)2]γ = 72.776 (4)°
Mr = 402.08V = 363.52 (6) Å3
Triclinic, P1Z = 1
a = 4.9290 (5) ÅMo Kα radiation
b = 6.4258 (6) ŵ = 1.10 mm−1
c = 12.2812 (10) ÅT = 298 K
α = 78.161 (3)°0.15 × 0.13 × 0.10 mm
β = 85.175 (3)°
Data collection top
Rigaku R-AXIS RAPID
diffractometer		1668 independent reflections
Absorption correction: empirical (using intensity measurements)
(ABSCOR; Higashi, 1995)		1066 reflections with I > 2σ(I)
Tmin = 0.852, Tmax = 0.898Rint = 0.050
3655 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0410 restraints
wR(F2) = 0.075H atoms treated by a mixture of independent and constrained refinement
S = 0.92Δρmax = 0.30 e Å−3
1668 reflectionsΔρmin = −0.34 e Å−3
122 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
Fe10.00000.00000.00000.0224 (2)
O50.3576 (5)−0.2580 (4)0.06771 (17)0.0314 (5)
H1W0.297 (7)−0.370 (6)0.097 (2)0.047*
H2W0.489 (7)−0.278 (6)0.026 (3)0.047*
N10.1698 (5)−0.0023 (4)−0.16828 (18)0.0237 (5)
C10.3247 (6)0.0920 (5)−0.2439 (2)0.0262 (7)
H10.40990.1967−0.23230.031*
N20.3439 (5)0.0184 (4)−0.33916 (18)0.0277 (6)
H2A0.43460.0598−0.39860.033*
C20.1936 (6)−0.1351 (5)−0.3258 (2)0.0233 (7)
C30.0869 (6)−0.1468 (4)−0.2178 (2)0.0216 (6)
C40.1805 (6)−0.2443 (5)−0.4200 (2)0.0279 (7)
O10.3050 (5)−0.2040 (4)−0.50906 (15)0.0409 (6)
O20.0250 (6)−0.3870 (4)−0.40319 (18)0.0551 (7)
H2−0.0479−0.3917−0.34050.083*
C5−0.0966 (6)−0.2761 (5)−0.1514 (2)0.0236 (6)
O3−0.1770 (4)−0.4089 (3)−0.19419 (15)0.0328 (5)
O4−0.1626 (4)−0.2417 (3)−0.05321 (14)0.0262 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Fe10.0257 (4)0.0281 (4)0.0170 (3)−0.0135 (3)0.0060 (3)−0.0062 (3)
O50.0304 (14)0.0328 (14)0.0320 (12)−0.0157 (12)0.0077 (9)−0.0019 (10)
N10.0283 (14)0.0267 (14)0.0211 (11)−0.0140 (12)0.0014 (10)−0.0070 (10)
C10.0309 (18)0.0317 (18)0.0225 (14)−0.0184 (15)0.0019 (13)−0.0067 (13)
N20.0314 (15)0.0371 (16)0.0195 (11)−0.0195 (13)0.0077 (10)−0.0058 (11)
C20.0284 (17)0.0243 (17)0.0194 (14)−0.0103 (14)0.0006 (12)−0.0056 (12)
C30.0225 (16)0.0235 (16)0.0191 (13)−0.0078 (14)0.0012 (11)−0.0034 (12)
C40.0343 (19)0.0304 (18)0.0244 (16)−0.0168 (16)0.0028 (13)−0.0077 (13)
O10.0533 (16)0.0563 (16)0.0234 (11)−0.0307 (14)0.0124 (11)−0.0134 (11)
O20.073 (2)0.0626 (18)0.0436 (14)−0.0405 (16)0.0158 (13)−0.0184 (14)
C50.0250 (17)0.0234 (17)0.0239 (15)−0.0083 (14)−0.0014 (12)−0.0052 (13)
O30.0458 (14)0.0345 (13)0.0281 (10)−0.0261 (12)0.0047 (10)−0.0087 (9)
O40.0302 (12)0.0313 (12)0.0218 (10)−0.0179 (11)0.0088 (9)−0.0057 (9)
Geometric parameters (Å, º) top
Fe1—O52.121 (2)C1—H10.9300
Fe1—O5i2.121 (2)N2—C21.377 (3)
Fe1—N1i2.165 (2)N2—H2A0.8600
Fe1—N12.165 (2)C2—C31.380 (3)
Fe1—O4i2.1732 (16)C2—C41.487 (3)
Fe1—O42.1732 (16)C3—C51.489 (4)
O5—H1W0.86 (3)C4—O11.226 (3)
O5—H2W0.79 (3)C4—O21.335 (3)
N1—C11.317 (3)O2—H20.8200
N1—C31.377 (3)C5—O31.257 (3)
C1—N21.336 (3)C5—O41.269 (3)
O5—Fe1—O5i180.00 (11)N1—C1—N2111.5 (2)
O5—Fe1—N1i87.70 (9)N1—C1—H1124.3
O5i—Fe1—N1i92.30 (9)N2—C1—H1124.3
O5—Fe1—N192.30 (9)C1—N2—C2108.2 (2)
O5i—Fe1—N187.70 (9)C1—N2—H2A125.9
N1i—Fe1—N1180.00 (16)C2—N2—H2A125.9
O5—Fe1—O4i90.06 (7)N2—C2—C3105.0 (2)
O5i—Fe1—O4i89.94 (7)N2—C2—C4119.4 (2)
N1i—Fe1—O4i76.79 (7)C3—C2—C4135.6 (2)
N1—Fe1—O4i103.21 (7)N1—C3—C2109.3 (2)
O5—Fe1—O489.94 (7)N1—C3—C5118.0 (2)
O5i—Fe1—O490.06 (7)C2—C3—C5132.7 (2)
N1i—Fe1—O4103.21 (7)O1—C4—O2121.8 (2)
N1—Fe1—O476.79 (7)O1—C4—C2121.5 (2)
O4i—Fe1—O4180.00 (12)O2—C4—C2116.7 (2)
Fe1—O5—H1W107 (2)C4—O2—H2109.5
Fe1—O5—H2W113 (3)O3—C5—O4124.3 (3)
H1W—O5—H2W117 (3)O3—C5—C3119.6 (2)
C1—N1—C3106.0 (2)O4—C5—C3116.1 (2)
C1—N1—Fe1141.85 (18)C5—O4—Fe1116.99 (16)
C3—N1—Fe1112.14 (17)
Symmetry code: (i) −x, −y, −z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O5—H1W···O3ii0.86 (3)1.86 (3)2.705 (3)165 (3)
O5—H2W···O4iii0.79 (3)1.95 (3)2.702 (3)158 (3)
N2—H2A···O1iv0.861.952.767 (3)157
O2—H2···O30.821.852.665 (3)174
Symmetry codes: (ii) −x, −y−1, −z; (iii) x+1, y, z; (iv) −x+1, −y, −z−1.

Experimental details

Crystal data
Chemical formula[Fe(C5H3N2O4)2(H2O)2]
Mr402.08
Crystal system, space groupTriclinic, P1
Temperature (K)298
a, b, c (Å)4.9290 (5), 6.4258 (6), 12.2812 (10)
α, β, γ (°)78.161 (3), 85.175 (3), 72.776 (4)
V (Å3)363.52 (6)
Z1
Radiation typeMo Kα
µ (mm−1)1.10
Crystal size (mm)0.15 × 0.13 × 0.10
Data collection
DiffractometerRigaku R-AXIS RAPID
Absorption correctionEmpirical (using intensity measurements)
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.852, 0.898
No. of measured, independent and
observed [I > 2σ(I)] reflections		3655, 1668, 1066
Rint0.050
(sin θ/λ)max (Å−1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.075, 0.92
No. of reflections1668
No. of parameters122
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.30, −0.34

Computer programs: RAPID-AUTO (Rigaku, 1998), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O5—H1W···O3i0.86 (3)1.86 (3)2.705 (3)165 (3)
O5—H2W···O4ii0.79 (3)1.95 (3)2.702 (3)158 (3)
N2—H2A···O1iii0.861.952.767 (3)157
O2—H2···O30.821.852.665 (3)174
Symmetry codes: (i) −x, −y−1, −z; (ii) x+1, y, z; (iii) −x+1, −y, −z−1.
 

Acknowledgements

This study was supported financially by the Inter-University Cooperative Research Program of the Institute for Materials Research, Tohoku University (proposal No. 11 K0091).

References

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 8| August 2012| Pages m1093-m1094
https://doi.org/10.1107/S1600536812031753
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