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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 67| Part 5| May 2011| Page m583
doi:10.1107/S1600536811012992

Di­aqua­bis­­(4-carb­­oxy-2-ethyl-1H-imidazole-5-carboxyl­ato-κ2N3,O4)zinc N,N-di­methyl­formamide disolvate

Cheng-Jun Haoa* and Hui Xiea

aCollege of Chemistry and Chemical Engineering, Pingdingshan University, Pingdingshan 467000, People's Republic of China.
*Correspondence e-mail: haochengjun2008@163.com

(Received 30 March 2011; accepted 7 April 2011; online 13 April 2011)

In the title compound, [Zn(C7H7N2O4)2(H2O)2]·2C3H7NO, the ZnII ion, which lies on a center of inversion, is coordinated by two O atoms and two N atoms from two 4-carboxy-2-ethyl-1H-imid­azole-5-carboxyl­ato anions and two water O atoms in an octa­hedral environment, Each 4-carboxy-2-ethyl-1H-imid­azole-5-carboxyl­ato ligand adopts a bidentate chelating mode to the ZnII ion, forming two five-membered metalla rings. In the crystal, a two-dimensional framework parallel to (010) is formed by N—H⋯O and O—H⋯O hydrogen bonds.

Related literature

For the properties of complexes derived from imidazole-4,5-dicarboxylic acid, see: Maji et al. (2005[Maji, T. K., Mostafa, G., Chang, H. C. & Kitagawa, S. (2005). Chem. Commun. pp. 2436-2438.]); Yang & Zhang (2006[Yang, R. Q. & Zhang, X. M. (2006). Inorg. Chem. 45, 4801-4810]). For our previous work based on 2-ethyl-4,5-imidazole­dicarboxyl­ate, see: Tian et al. (2010[Tian, D. M., Li, Y. F. & Hao, C. J. (2010). Z. Kristallogr. New Cryst. Struct. 225, 403-404]).

[Scheme 1]

Experimental

Crystal data

  • [Zn(C7H7N2O4)2(H2O)2]·2C3H7NO

  • Mr = 613.89

  • Monoclinic, P 21 /c

  • a = 7.2817 (8) Å

  • b = 20.660 (2) Å

  • c = 9.3623 (9) Å

  • β = 111.846 (7)°

  • V = 1307.3 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 1.01 mm−1

  • T = 296 K

  • 0.53 × 0.41 × 0.31 mm
Data collection

  • Bruker APEXII area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.616, Tmax = 0.744

  • 10742 measured reflections

  • 2619 independent reflections

  • 2083 reflections with I > 2σ(I)

  • Rint = 0.037
Refinement

  • R[F2 > 2σ(F2)] = 0.034

  • wR(F2) = 0.086

  • S = 1.02

  • 2619 reflections

  • 181 parameters

  • 3 restraints

  • H-atom parameters constrained

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.36 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1W—H1W⋯O1i 0.85 1.95 2.798 (2) 173
O1W—H2W⋯O1ii 0.85 2.06 2.894 (2) 168
O3—H3⋯O2 0.85 1.62 2.473 (2) 177
N2—H2⋯O5 0.86 1.85 2.689 (2) 166
Symmetry codes: (i) -x+2, -y, -z+1; (ii) x+1, y, z+1.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811012992/nk2096sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811012992/nk2096Isup2.hkl

checkCIF report


Comment top

Imidazole-4,5-dicarboxylic acid (H3Imda) can be deprotonated to generate three types of anions, namely Imda3-, HImda2- and H2Imda-and react with metal ions to form fascinating structures with different structures and useful properties (Maji et al., 2005; Yang et al., 2006). In previous studies, we have obtained a CaIIcomplex based on 2-ethyl-1H-imidazole-4,5-dicarboxylate under hydrothermal conditions (Tian et al., 2010). In this paper, we report a new ZnII complex.

The title compound, [Zn(C7H7N2O4)2 (H2O)2].2C3H7NO, as shown in Fig. 1, is a discrete complex, consisting of one ZnII ion, two mono-deprotonated 2-ethyl-1H-imidazole-4,5-dicarboxy anions and two water molecules. Each ZnII ion is six-coordinated in an octahedral coordination environment, formed by two oxygen atoms(O4,O4i) and two nitrogen atoms (N1,N1i)from two 2-ethyl-4,5-imidazoledicarboxylate ligands in the equatorial plane and two water molecules in the apical sites (symmetry codes: -x + 2, -y, -z + 1).the Zn—O bond distances are 2.1461 (18) Å and 2.2013 (18) Å, and Zn—N bond distances are 2.0683 (19) Å. Each 2-ethyl-4,5-imidazoledicarboxylate ligand chelates the ZnII ion in a bidentate coordination mode through its imidazole nitrogen atom and carboxylate oxygen atom. Extensive hydrogen-bonding interactions (N—H···O and O—H···O), generate a two-dimensional structure.

Related literature top

For the properties of imidazole-4,5-dicarboxylic complexes, see: Maji et al. (2005); Yang & Zhang (2006). For our previous work based on 2-ethyl-4,5-imidazoledicarboxylate, see: Tian et al. (2010).

Experimental top

A mixture of ZnNO3 (0.5 mmol, 0.06 g) and 2-ethyl-1H-imidazole-4,5-dicarboxylic acid(0.5 mmol, 0.95 g) dissolved in 10 ml C3H7NO, and then the solution was sealed in an autoclave equipped with a Teflon liner (25 ml) and then heated at 373k for 3 days. After slowly cooling down to room temperature, colourless crystals of the title compound were obtained directly from the solution.

Refinement top

Carbon and nitrogen bound H atoms were placed at calculated positions and were treated as riding on the parent C or N atoms with C—H = 0.93 Å, N—H = 0.86 Å, and with Uiso(H) = 1.2 Ueq(C, N). H atoms of the water molecule were located in a difference Fourier map and refined as riding with an O—H distance restraint of 0.84 (1) Å, with Uiso(H) = 1.5 Ueq. The H···H distances within the water molecules were restraint to 1.39 (1) Å. Carboxyl H atoms were located in a difference Fourier map and refined as riding with an O—H distance constraint of 0.85 Å, with Uiso(H) = 1.2 Ueq.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The structure of the title compound, with 30% probability displacement ellipsoids (H atoms are omitted for clarity). [Symmetry codes: (i) -x + 2, -y, -z + 1.]
Diaquabis(4-carboxy-2-ethyl-1H-imidazole-5-carboxylato- κ2N3,O4)zinc N,N-dimethylformamide disolvate top
Crystal data top
[Zn(C7H7N2O4)2(H2O)2]·2C3H7NOF(000) = 640
Mr = 613.89Dx = 1.560 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 5837 reflections
a = 7.2817 (8) Åθ = 2.8–27.9°
b = 20.660 (2) ŵ = 1.01 mm−1
c = 9.3623 (9) ÅT = 296 K
β = 111.846 (7)°Block, colourless
V = 1307.3 (2) Å30.53 × 0.41 × 0.31 mm
Z = 2
Data collection top
Bruker APEXII area-detector
diffractometer		2619 independent reflections
Radiation source: fine-focus sealed tube2083 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.037
ϕ and ω scanθmax = 26.2°, θmin = 2.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −9→8
Tmin = 0.616, Tmax = 0.744k = −25→25
10742 measured reflectionsl = −11→11
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)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.086H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0387P)2 + 0.6624P]
where P = (Fo2 + 2Fc2)/3
2619 reflections(Δ/σ)max < 0.001
181 parametersΔρmax = 0.22 e Å−3
3 restraintsΔρmin = −0.36 e Å−3
Crystal data top
[Zn(C7H7N2O4)2(H2O)2]·2C3H7NOV = 1307.3 (2) Å3
Mr = 613.89Z = 2
Monoclinic, P21/cMo Kα radiation
a = 7.2817 (8) ŵ = 1.01 mm−1
b = 20.660 (2) ÅT = 296 K
c = 9.3623 (9) Å0.53 × 0.41 × 0.31 mm
β = 111.846 (7)°
Data collection top
Bruker APEXII area-detector
diffractometer		2619 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2083 reflections with I > 2σ(I)
Tmin = 0.616, Tmax = 0.744Rint = 0.037
10742 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0343 restraints
wR(F2) = 0.086H-atom parameters constrained
S = 1.02Δρmax = 0.22 e Å−3
2619 reflectionsΔρmin = −0.36 e Å−3
181 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
Zn11.00000.00001.00000.02973 (13)
O10.6355 (3)−0.00930 (9)0.25342 (18)0.0414 (4)
O1W1.2808 (2)0.03585 (9)1.00911 (17)0.0383 (4)
H1W1.29820.02550.92720.057*
H2W1.37290.01971.08630.057*
O20.7948 (3)−0.09580 (9)0.38356 (18)0.0424 (4)
O30.9815 (3)−0.12960 (8)0.65214 (18)0.0392 (4)
H30.9214−0.11760.55950.047*
O41.0464 (2)−0.08767 (8)0.88405 (17)0.0358 (4)
N10.8675 (3)0.02603 (9)0.77101 (19)0.0263 (4)
N20.7049 (3)0.05738 (9)0.5331 (2)0.0287 (4)
H20.63730.08140.45650.034*
C10.7687 (3)0.07446 (11)0.6824 (2)0.0280 (5)
C20.8660 (3)−0.02367 (11)0.6730 (2)0.0247 (4)
C30.7660 (3)−0.00476 (11)0.5237 (2)0.0274 (5)
C40.9705 (3)−0.08386 (11)0.7418 (2)0.0292 (5)
C50.7267 (3)−0.03848 (12)0.3751 (2)0.0326 (5)
C60.7387 (4)0.14021 (12)0.7351 (3)0.0407 (6)
H6A0.78230.14030.84640.049*
H6B0.59860.15040.69340.049*
C70.8514 (5)0.19225 (14)0.6854 (4)0.0594 (8)
H7A0.98950.18150.72300.089*
H7B0.83420.23330.72690.089*
H7C0.80130.19470.57510.089*
O50.4712 (3)0.14244 (10)0.32830 (19)0.0504 (5)
N30.4143 (3)0.18961 (10)0.0978 (2)0.0412 (5)
C80.5131 (4)0.15203 (13)0.2144 (3)0.0428 (6)
H8A0.62390.13090.21040.051*
C90.4683 (6)0.1927 (2)−0.0361 (4)0.0754 (10)
H9A0.59860.1751−0.01090.113*
H9B0.46650.2369−0.06790.113*
H9C0.37550.1680−0.11820.113*
C100.2338 (5)0.22132 (16)0.0909 (4)0.0654 (9)
H10A0.22200.21840.18950.098*
H10B0.12230.20050.01470.098*
H10C0.23740.26600.06400.098*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Zn10.0328 (2)0.0381 (2)0.01527 (18)0.00315 (17)0.00554 (15)0.00143 (15)
O10.0407 (10)0.0605 (12)0.0179 (8)0.0054 (8)0.0051 (8)0.0017 (8)
O1W0.0322 (9)0.0579 (12)0.0227 (8)−0.0008 (8)0.0078 (7)0.0013 (8)
O20.0510 (11)0.0429 (11)0.0271 (9)0.0046 (9)0.0075 (8)−0.0077 (7)
O30.0489 (10)0.0363 (9)0.0271 (9)0.0113 (8)0.0079 (8)−0.0007 (7)
O40.0433 (10)0.0374 (9)0.0211 (8)0.0090 (8)0.0055 (7)0.0040 (7)
N10.0285 (10)0.0322 (10)0.0167 (9)0.0036 (8)0.0065 (8)0.0015 (7)
N20.0295 (10)0.0336 (11)0.0196 (9)0.0060 (8)0.0053 (8)0.0066 (8)
C10.0283 (12)0.0331 (12)0.0218 (11)0.0025 (9)0.0082 (10)0.0026 (9)
C20.0250 (11)0.0297 (11)0.0183 (10)0.0009 (9)0.0068 (9)0.0007 (8)
C30.0251 (11)0.0359 (12)0.0204 (10)−0.0016 (10)0.0075 (9)0.0005 (9)
C40.0292 (12)0.0323 (12)0.0252 (12)0.0008 (10)0.0092 (10)−0.0001 (9)
C50.0278 (12)0.0450 (15)0.0230 (12)−0.0046 (11)0.0072 (10)−0.0024 (10)
C60.0472 (15)0.0407 (15)0.0313 (13)0.0133 (12)0.0114 (12)−0.0014 (11)
C70.067 (2)0.0383 (16)0.064 (2)−0.0033 (15)0.0142 (17)−0.0061 (14)
O50.0557 (12)0.0593 (13)0.0310 (10)0.0156 (10)0.0101 (9)0.0128 (8)
N30.0462 (12)0.0405 (12)0.0304 (11)0.0003 (10)0.0069 (10)0.0045 (9)
C80.0419 (15)0.0422 (15)0.0390 (15)0.0083 (12)0.0090 (12)0.0028 (12)
C90.091 (3)0.095 (3)0.0440 (18)−0.008 (2)0.0296 (19)0.0128 (17)
C100.066 (2)0.062 (2)0.0517 (18)0.0231 (17)0.0028 (16)0.0102 (15)
Geometric parameters (Å, º) top
Zn1—N12.0680 (17)C2—C41.475 (3)
Zn1—N1i2.0680 (17)C3—C51.485 (3)
Zn1—O1Wi2.1464 (16)C6—C71.526 (4)
Zn1—O1W2.1464 (16)C6—H6A0.9700
Zn1—O42.2013 (16)C6—H6B0.9700
Zn1—O4i2.2013 (16)C7—H7A0.9600
O1—C51.241 (3)C7—H7B0.9600
O1W—H1W0.8501C7—H7C0.9600
O1W—H2W0.8500O5—C81.230 (3)
O2—C51.275 (3)N3—C81.314 (3)
O3—C41.286 (3)N3—C101.448 (4)
O3—H30.8500N3—C91.448 (3)
O4—C41.240 (3)C8—H8A0.9300
N1—C11.328 (3)C9—H9A0.9600
N1—C21.375 (3)C9—H9B0.9600
N2—C11.346 (3)C9—H9C0.9600
N2—C31.372 (3)C10—H10A0.9600
N2—H20.8600C10—H10B0.9600
C1—C61.489 (3)C10—H10C0.9600
C2—C31.371 (3)
N1—Zn1—N1i180.0O4—C4—C2118.3 (2)
N1—Zn1—O1Wi88.77 (7)O3—C4—C2118.78 (19)
N1i—Zn1—O1Wi91.23 (6)O1—C5—O2124.8 (2)
N1—Zn1—O1W91.23 (6)O1—C5—C3118.9 (2)
N1i—Zn1—O1W88.77 (7)O2—C5—C3116.3 (2)
O1Wi—Zn1—O1W180.0C1—C6—C7112.3 (2)
N1—Zn1—O478.50 (6)C1—C6—H6A109.1
N1i—Zn1—O4101.50 (6)C7—C6—H6A109.1
O1Wi—Zn1—O490.87 (6)C1—C6—H6B109.1
O1W—Zn1—O489.13 (6)C7—C6—H6B109.1
N1—Zn1—O4i101.50 (6)H6A—C6—H6B107.9
N1i—Zn1—O4i78.50 (6)C6—C7—H7A109.5
O1Wi—Zn1—O4i89.13 (6)C6—C7—H7B109.5
O1W—Zn1—O4i90.87 (6)H7A—C7—H7B109.5
O4—Zn1—O4i180.000 (1)C6—C7—H7C109.5
Zn1—O1W—H1W109.7H7A—C7—H7C109.5
Zn1—O1W—H2W109.7H7B—C7—H7C109.5
H1W—O1W—H2W109.5C8—N3—C10120.8 (2)
C4—O3—H3108.6C8—N3—C9120.2 (3)
C4—O4—Zn1112.88 (14)C10—N3—C9118.4 (2)
C1—N1—C2106.13 (17)O5—C8—N3125.4 (2)
C1—N1—Zn1141.17 (15)O5—C8—H8A117.3
C2—N1—Zn1112.51 (14)N3—C8—H8A117.3
C1—N2—C3108.49 (18)N3—C9—H9A109.5
C1—N2—H2125.8N3—C9—H9B109.5
C3—N2—H2125.8H9A—C9—H9B109.5
N1—C1—N2110.41 (19)N3—C9—H9C109.5
N1—C1—C6126.4 (2)H9A—C9—H9C109.5
N2—C1—C6123.2 (2)H9B—C9—H9C109.5
C3—C2—N1109.71 (19)N3—C10—H10A109.5
C3—C2—C4132.7 (2)N3—C10—H10B109.5
N1—C2—C4117.60 (18)H10A—C10—H10B109.5
C2—C3—N2105.25 (18)N3—C10—H10C109.5
C2—C3—C5131.7 (2)H10A—C10—H10C109.5
N2—C3—C5123.0 (2)H10B—C10—H10C109.5
O4—C4—O3122.9 (2)
Symmetry code: (i) −x+2, −y, −z+2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···O1ii0.851.952.798 (2)173
O1W—H2W···O1iii0.852.062.894 (2)168
O3—H3···O20.851.622.473 (2)177
N2—H2···O50.861.852.689 (2)166
Symmetry codes: (ii) −x+2, −y, −z+1; (iii) x+1, y, z+1.

Experimental details

Crystal data
Chemical formula[Zn(C7H7N2O4)2(H2O)2]·2C3H7NO
Mr613.89
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)7.2817 (8), 20.660 (2), 9.3623 (9)
β (°) 111.846 (7)
V (Å3)1307.3 (2)
Z2
Radiation typeMo Kα
µ (mm−1)1.01
Crystal size (mm)0.53 × 0.41 × 0.31
Data collection
DiffractometerBruker APEXII area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.616, 0.744
No. of measured, independent and
observed [I > 2σ(I)] reflections		10742, 2619, 2083
Rint0.037
(sin θ/λ)max (Å−1)0.621
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.034, 0.086, 1.02
No. of reflections2619
No. of parameters181
No. of restraints3
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.22, −0.36

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···O1i0.851.952.798 (2)173
O1W—H2W···O1ii0.852.062.894 (2)168
O3—H3···O20.851.622.473 (2)177
N2—H2···O50.861.852.689 (2)166
Symmetry codes: (i) −x+2, −y, −z+1; (ii) x+1, y, z+1.
 

Acknowledgements

The authors acknowledge Pingdingshan University for support of this work.

References

First citationBruker (2007). APEX2 and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationMaji, T. K., Mostafa, G., Chang, H. C. & Kitagawa, S. (2005). Chem. Commun. pp. 2436–2438.  Web of Science CSD CrossRef Google Scholar
 First citationSheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.  Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationTian, D. M., Li, Y. F. & Hao, C. J. (2010). Z. Kristallogr. New Cryst. Struct. 225, 403–404  CAS Google Scholar
 First citationYang, R. Q. & Zhang, X. M. (2006). Inorg. Chem. 45, 4801–4810  Web of Science PubMed Google Scholar

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 5| May 2011| Page m583
doi:10.1107/S1600536811012992
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