Bis(imidazolium) di-μ-pyrazole-3,5-dicarboxyl­ato(3–)-bis­[diaqua­zinc(II)]

In the title compound, (C₃H₅N₂)₂[Zn₂(C₅HN₂O₄)₂(H₂O)₄], two 3,5-pyrazole­dicarboxyl­ate trianions and two water mol­ecules are coordinated to the Zn atom and the geometry is octa­hedral. Each pair of Zn^II ions is bridged by two 3,5-pyrazole­dicarboxyl­ate trianions, forming a centrosymmetric binuclear complex dianion. In the crystal structure, the cations and anions are linked by O—H...O and N—H...O hydrogen bonds to form a network structure.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.027
• wR factor = 0.071
• Data-to-parameter ratio = 11.5

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X)  Zn1    -   O4_a    ..      12.93 su

Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Zn1    -   O2      ..       9.89 su

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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S1. Comment

The design and synthesis of supramolecular inorganic architectures exhibiting novel properties is providing exciting new opportunities in many fields of research (Swiegers & Malefetse, 2002; Johnson & Raymond, 2001; Hof et al., 2002). In the synthesis of supramolecular inorganic architectures by design, the assembly of molecular units in predefined arrangements is a key goal (Desiraju, 1995, 1997; Braga et al., 1998). Directional intermolecular interactions are the primary tools in achieving this goal and hydrogen bonding is currently the best tool amongst them (Zaworotko, 1997; Braga & Grepioni, 2000). We report here on the structure of the title compound, (I), which consists of two imidazolium cations and a centrosymmetric [Zn(C₅HO₄N₂)(H₂O)₂]₂²⁻ dianion.

The molecular structure of compound (I) is shown in Fig. 1, and selected bond distances and angles are given in Table 1. The geometry around each Zn atom is octahedral, arising from coordination by two 3,5-pyrazoledicarboxylate trianions and two water molecules. A carboxylate O atom and an N atom, of one of the 3,5-pyrazoledicarboxylate trianions, are chelated to a Zn atom. Each pair of Zn^II ions is bridged by two 3,5-pyrazoledicarboxylate trianions, forming a centrosymmetric binuclear complex anion, as shown in Fig. 1.

In the crystal structure the cations and anions interact through O—H···O and N—H···O hydrogen bonds (Table 2) to generate a three-dimensional network structure (Fig. 2).

S2. Experimental

The title compound was synthesized by the hydrothermal method from a mixture of zinc nitrate hexahydrate (0.06 g, 0.2 mmol), pyrazole-3,5-dicarboxylic acid (0.08 g, 0.4 mmol), 1,1'-carbonyl diimidazole (0.03 g, 0.2 mmol) and water (8.0 ml) in a 15.0 ml telfon-lined stainless steel reactor. The solution was heated at 423 K for two days. After reaction, the vessel was slowly cooled to room temperature to give colorless crystals. Prism-like crystals were collected, washed with distilled water and dried in air. As shown by the present crystal structure analysis, the 1,1'-carbonyldiimidazole had decomposed into two imidazoles, and a proton had been added to an imidazole, so formming an imidazole cation to balance the charges.

S3. Refinement

All H atoms were positioned geometrically and allowed to ride on their parent atoms with distances of O—H = 0.82 Å, C—H = 0.93 Å and N—H = 0.86 Å, with U_iso(H) = 1.2U_eq(parent O, C or N-atom).

Computing details

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Bruker, 2002); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. The asymmetric unit of compound (I), showing the atom numbering and displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. A perspective view along the a axis of the crystal packing of compound (I), with the hydrogen bonds shown as dashed lines.

Bis(imidazolium) di-µ-pyrazole-3,5-dicarboxylato(3-)-bis[diaquazinc(II)]

Crystal data

(C3H5N2)2[Zn2(C5HN2O4)2(H2O)4]	Z = 1
Mr = 647.18	F(000) = 328
Triclinic, P1	Dx = 1.892 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.3068 (6) Å	Cell parameters from 328 reflections
b = 9.2879 (7) Å	θ = 2.3–25.1°
c = 9.7233 (8) Å	µ = 2.19 mm^−1
α = 94.621 (1)°	T = 298 K
β = 110.496 (1)°	Prism, colorless
γ = 109.477 (1)°	0.34 × 0.20 × 0.10 mm
V = 568.00 (8) Å^3

Data collection

Bruker APEX area-detector diffractometer	2000 independent reflections
Radiation source: fine-focus sealed tube	1945 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.012
ϕ and ω scans	θmax = 25.1°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Bruker, 2002)	h = −5→8
Tmin = 0.60, Tmax = 0.80	k = −11→11
3010 measured reflections	l = −11→10

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.027	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.071	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0312P)^2 + 0.6561P] where P = (Fo^2 + 2Fc^2)/3
2000 reflections	(Δ/σ)max = 0.001
174 parameters	Δρmax = 0.36 e Å^−3
0 restraints	Δρmin = −0.36 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O5	0.7296 (3)	0.1786 (2)	0.5571 (3)	0.0503 (6)
H5A	0.7562	0.1079	0.5233	0.076*
H5B	0.6391	0.1870	0.5849	0.076*
O6	1.2673 (3)	0.5181 (2)	0.8414 (2)	0.0305 (4)
H6A	1.3718	0.5095	0.8340	0.046*
H6B	1.2567	0.4953	0.9188	0.046*
Zn1	0.99994 (4)	0.37397 (3)	0.65831 (3)	0.02091 (12)
O1	0.6613 (3)	0.5293 (2)	0.8800 (2)	0.0326 (4)
O2	0.8408 (3)	0.3972 (2)	0.8244 (2)	0.0269 (4)
O3	0.6304 (3)	0.8950 (2)	0.3948 (2)	0.0321 (4)
O4	0.8379 (3)	0.8161 (2)	0.3126 (2)	0.0359 (5)
N1	0.8712 (3)	0.5371 (2)	0.6020 (2)	0.0204 (4)
N2	0.8706 (3)	0.6225 (2)	0.4969 (2)	0.0213 (4)
C1	0.7516 (4)	0.4934 (3)	0.8024 (3)	0.0218 (5)
C2	0.7615 (4)	0.5722 (3)	0.6763 (3)	0.0196 (5)
C3	0.6856 (4)	0.6819 (3)	0.6175 (3)	0.0219 (5)
H3A	0.6045	0.7261	0.6470	0.026*
C4	0.7585 (4)	0.7104 (3)	0.5047 (3)	0.0203 (5)
C5	0.7401 (4)	0.8158 (3)	0.3966 (3)	0.0236 (5)
N4	0.7717 (4)	0.1548 (3)	−0.0354 (3)	0.0382 (6)
H4	0.7807	0.2415	−0.0634	0.046*
C7	0.7393 (5)	0.0190 (4)	−0.1234 (4)	0.0441 (8)
H7	0.7242	0.0038	−0.2231	0.053*
C6	0.7332 (5)	−0.0884 (4)	−0.0393 (4)	0.0414 (7)
H6	0.7121	−0.1922	−0.0695	0.050*
N3	0.7637 (4)	−0.0165 (3)	0.0986 (3)	0.0373 (6)
H3B	0.7674	−0.0599	0.1738	0.045*
C8	0.7869 (5)	0.1315 (4)	0.0989 (4)	0.0378 (7)
H8	0.8100	0.2055	0.1799	0.045*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O5	0.0339 (11)	0.0302 (11)	0.0842 (18)	0.0041 (9)	0.0341 (12)	−0.0129 (11)
O6	0.0271 (9)	0.0491 (12)	0.0227 (9)	0.0193 (9)	0.0132 (8)	0.0126 (8)
Zn1	0.02608 (18)	0.02330 (18)	0.02174 (17)	0.01282 (13)	0.01484 (13)	0.01018 (12)
O1	0.0347 (10)	0.0564 (13)	0.0243 (9)	0.0263 (10)	0.0210 (8)	0.0204 (9)
O2	0.0336 (10)	0.0270 (9)	0.0294 (10)	0.0158 (8)	0.0173 (8)	0.0155 (8)
O3	0.0343 (10)	0.0269 (10)	0.0415 (11)	0.0186 (8)	0.0147 (9)	0.0136 (8)
O4	0.0425 (11)	0.0472 (12)	0.0375 (11)	0.0251 (10)	0.0270 (9)	0.0277 (10)
N1	0.0266 (11)	0.0243 (11)	0.0185 (10)	0.0140 (9)	0.0131 (8)	0.0099 (8)
N2	0.0279 (11)	0.0254 (11)	0.0216 (10)	0.0153 (9)	0.0162 (9)	0.0117 (9)
C1	0.0187 (12)	0.0266 (13)	0.0190 (12)	0.0068 (10)	0.0079 (10)	0.0074 (10)
C2	0.0203 (11)	0.0227 (12)	0.0189 (11)	0.0093 (10)	0.0102 (9)	0.0062 (9)
C3	0.0246 (12)	0.0265 (13)	0.0223 (12)	0.0145 (10)	0.0135 (10)	0.0066 (10)
C4	0.0224 (12)	0.0220 (12)	0.0215 (12)	0.0122 (10)	0.0105 (10)	0.0072 (10)
C5	0.0255 (12)	0.0224 (12)	0.0236 (13)	0.0092 (10)	0.0098 (10)	0.0091 (10)
N4	0.0413 (14)	0.0329 (13)	0.0475 (15)	0.0169 (11)	0.0198 (12)	0.0257 (12)
C7	0.056 (2)	0.0475 (19)	0.0365 (17)	0.0252 (16)	0.0203 (15)	0.0192 (14)
C6	0.0504 (19)	0.0343 (16)	0.0414 (17)	0.0176 (14)	0.0179 (15)	0.0153 (13)
N3	0.0394 (14)	0.0366 (14)	0.0355 (13)	0.0107 (11)	0.0151 (11)	0.0230 (11)
C8	0.0373 (16)	0.0328 (15)	0.0412 (17)	0.0092 (13)	0.0167 (13)	0.0124 (13)

Geometric parameters (Å, º)

O5—Zn1	2.031 (2)	N2—C4	1.350 (3)
O5—H5A	0.8200	N2—Zn1^i	2.040 (2)
O5—H5B	0.8201	C1—C2	1.488 (3)
O6—Zn1	2.0528 (18)	C2—C3	1.386 (3)
O6—H6A	0.8200	C3—C4	1.385 (3)
O6—H6B	0.8204	C3—H3A	0.9300
Zn1—N2^i	2.040 (2)	C4—C5	1.495 (3)
Zn1—N1	2.050 (2)	N4—C8	1.313 (4)
Zn1—O2	2.3303 (18)	N4—C7	1.366 (4)
Zn1—O4^i	2.417 (2)	N4—H4	0.8600
O1—C1	1.254 (3)	C7—C6	1.339 (4)
O2—C1	1.261 (3)	C7—H7	0.9300
O3—C5	1.253 (3)	C6—N3	1.356 (4)
O4—C5	1.259 (3)	C6—H6	0.9300
O4—Zn1^i	2.417 (2)	N3—C8	1.327 (4)
N1—N2	1.343 (3)	N3—H3B	0.8600
N1—C2	1.346 (3)	C8—H8	0.9300
Zn1—O5—H5A	109.5	O1—C1—C2	118.5 (2)
Zn1—O5—H5B	109.4	O2—C1—C2	116.3 (2)
H5A—O5—H5B	137.6	N1—C2—C3	109.8 (2)
Zn1—O6—H6A	109.5	N1—C2—C1	116.4 (2)
Zn1—O6—H6B	109.4	C3—C2—C1	133.8 (2)
H6A—O6—H6B	111.3	C4—C3—C2	104.0 (2)
O5—Zn1—N2^i	100.92 (9)	C4—C3—H3A	128.0
O5—Zn1—N1	98.09 (9)	C2—C3—H3A	128.0
N2^i—Zn1—N1	98.40 (8)	N2—C4—C3	109.8 (2)
O5—Zn1—O6	152.74 (10)	N2—C4—C5	116.4 (2)
N2^i—Zn1—O6	98.75 (8)	C3—C4—C5	133.7 (2)
N1—Zn1—O6	97.50 (8)	O3—C5—O4	125.1 (2)
O5—Zn1—O2	81.20 (8)	O3—C5—C4	119.0 (2)
N2^i—Zn1—O2	172.42 (7)	O4—C5—C4	115.9 (2)
N1—Zn1—O2	74.05 (7)	C8—N4—C7	108.9 (3)
O6—Zn1—O2	81.77 (7)	C8—N4—H4	125.6
O5—Zn1—O4^i	82.47 (8)	C7—N4—H4	125.6
N2^i—Zn1—O4^i	72.32 (7)	C6—C7—N4	107.2 (3)
N1—Zn1—O4^i	170.59 (7)	C6—C7—H7	126.4
O6—Zn1—O4^i	85.75 (7)	N4—C7—H7	126.4
O2—Zn1—O4^i	115.24 (6)	C7—C6—N3	106.8 (3)
C1—O2—Zn1	113.43 (15)	C7—C6—H6	126.6
C5—O4—Zn1^i	112.83 (16)	N3—C6—H6	126.6
N2—N1—C2	108.36 (19)	C8—N3—C6	109.2 (3)
N2—N1—Zn1	131.92 (15)	C8—N3—H3B	125.4
C2—N1—Zn1	119.72 (16)	C6—N3—H3B	125.4
N1—N2—C4	108.03 (19)	N4—C8—N3	107.9 (3)
N1—N2—Zn1^i	129.68 (15)	N4—C8—H8	126.0
C4—N2—Zn1^i	122.26 (16)	N3—C8—H8	126.0
O1—C1—O2	125.2 (2)
O5—Zn1—O2—C1	−100.34 (18)	O2—C1—C2—N1	−2.3 (3)
N1—Zn1—O2—C1	0.75 (16)	O1—C1—C2—C3	−1.6 (4)
O6—Zn1—O2—C1	101.03 (17)	O2—C1—C2—C3	180.0 (3)
O4^i—Zn1—O2—C1	−177.65 (16)	N1—C2—C3—C4	−0.5 (3)
O5—Zn1—N1—N2	−102.7 (2)	C1—C2—C3—C4	177.3 (3)
N2^i—Zn1—N1—N2	−0.4 (3)	N1—N2—C4—C3	0.2 (3)
O6—Zn1—N1—N2	99.7 (2)	Zn1^i—N2—C4—C3	178.54 (16)
O2—Zn1—N1—N2	178.9 (2)	N1—N2—C4—C5	179.6 (2)
O5—Zn1—N1—C2	76.30 (19)	Zn1^i—N2—C4—C5	−2.1 (3)
N2^i—Zn1—N1—C2	178.68 (18)	C2—C3—C4—N2	0.1 (3)
O6—Zn1—N1—C2	−81.27 (19)	C2—C3—C4—C5	−179.1 (3)
O2—Zn1—N1—C2	−2.09 (17)	Zn1^i—O4—C5—O3	−174.6 (2)
C2—N1—N2—C4	−0.5 (3)	Zn1^i—O4—C5—C4	4.9 (3)
Zn1—N1—N2—C4	178.62 (17)	N2—C4—C5—O3	177.0 (2)
C2—N1—N2—Zn1^i	−178.66 (17)	C3—C4—C5—O3	−3.8 (4)
Zn1—N1—N2—Zn1^i	0.5 (3)	N2—C4—C5—O4	−2.5 (3)
Zn1—O2—C1—O1	−177.7 (2)	C3—C4—C5—O4	176.7 (3)
Zn1—O2—C1—C2	0.5 (3)	C8—N4—C7—C6	0.6 (4)
N2—N1—C2—C3	0.6 (3)	N4—C7—C6—N3	−0.5 (4)
Zn1—N1—C2—C3	−178.64 (16)	C7—C6—N3—C8	0.3 (4)
N2—N1—C2—C1	−177.6 (2)	C7—N4—C8—N3	−0.4 (4)
Zn1—N1—C2—C1	3.1 (3)	C6—N3—C8—N4	0.0 (4)
O1—C1—C2—N1	176.0 (2)

Symmetry code: (i) −x+2, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5A···O3^ii	0.82	1.98	2.685 (3)	145
O5—H5B···O3^iii	0.82	1.95	2.706 (3)	153
O6—H6A···O1^iv	0.82	1.94	2.734 (3)	162
O6—H6B···O1^v	0.82	1.89	2.676 (2)	159
N4—H4···O2^vi	0.86	1.91	2.721 (3)	157
N3—H3B···O4^ii	0.86	1.89	2.709 (3)	159

Symmetry codes: (ii) x, y−1, z; (iii) −x+1, −y+1, −z+1; (iv) x+1, y, z; (v) −x+2, −y+1, −z+2; (vi) x, y, z−1.