Disodium bis(1,2,4,5-benzene­tetra­carboxyl­ato)­di­hydroxy­tetrazincate(II) pyrazine

The tetranuclear dianion of the title compound, Na₂[Zn₄(C₁₀H₂O₈)₂(OH)₂]·C₄H₄N₂, forms a network framework in which the Zn atom exists in a tetrahedral environment, as it is coordinated by the carboxyl O atoms belonging to three different (C₁₀H₂O₈)^4- anions as well as by the bridging OH group. Adjacent OH groups are linked together through the uncoordinated heterocycle, which lies on a site of 2/m symmetry. The octahedrally coordinated Na ion, which lies on a site of 2 symmetry, interacts with one O atom of the carboxyl group of two anions and with two O atoms of the ortho-carboxyl groups of two other anions.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.028
• wR factor = 0.072
• Data-to-parameter ratio = 12.5

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT029_ALERT_3_A _diffrn_measured_fraction_theta_full Low .....       0.95

Alert level C
PLAT041_ALERT_1_C Calc. and Rep. SumFormula Strings    Differ ..          ?
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ..          ?
PLAT045_ALERT_1_C Calculated and Reported Z Differ by ..........       2.00 Ratio
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .....          ?
PLAT164_ALERT_4_C Nr. of Refined C-H H-Atoms in Heavy-At Struct.          3
PLAT731_ALERT_1_C Bond    Calc     0.93(3), Rep   0.930(10) ....       3.00 su-Ratio
              C4   -H4      1.555   1.555
PLAT731_ALERT_1_C Bond    Calc     0.93(3), Rep   0.930(10) ....       3.00 su-Ratio
              C7   -H7      1.555   1.555

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

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

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S1. Comment

The 4,4'-bipyridine spacer molecule has been used in the formation of a plethora of adducts with zinc carboxylates; however, the spacer was not incorporated in hydrated disodium dihydrogen 1,2,4,5-benzenetetracarboxylatozinc (Wu et al., 2001) when the synthesis was performed under acidic conditions. The use of pyrazine in the metathetical reaction of the sodium salt of this acid and a zinc salt did not lead to the formation of an N-coordinated Zn complex either. The title complex, (I), is formally a hydroxide (Fig. 1), and the heterocycle merely serves as a connector that links adjacent groups together.

The compound adopts a network framework in which the Zn atom exits in a tetrahedral geometry, the atom being covalently bonded to the carboxyl O atoms belonging to three different [C₁₀H₂O₈]²⁻ dianions and to the bridging OH group. Adjacent OH groups are linked together through the lattice heterocycle (Fig. 2). The octahedrally coordinated Na atom interacts with one O atom of the carboxyl group of two dianions and with two O atoms of the ortho-carboxyl groups of two other dianions (Fig. 3).

In the assembly of coordination polymers the use of sodium hydroxide to deprotonate the carboxylic acids sometimes furnishes compounds having sodium atoms incorporated into the crystal structure (Robl, 1992; Wu et al., 2001; Yang et al., 2002) because the Na⁺ cation is able to form strong bonds with carboxylate groups or with water. Furthermore, it serves to compensate for the negative charge of the frameworks.

S2. Experimental

1,2,4,5-Benzenetetracarboxylic acid anhydride (pyromellitic anhydride, 0.22 g, 1 mmol) and sodium hydroxide (0.16 g, 4 mmol) were dissolved in water (15 ml), and to the solution was added zinc dinitrate hexahydrate (0.59 g, 2 mmol) and pyrazine (0.16 g, 2 mmol) dissolved in water (5 ml). The mixturen was placed in a 20 ml Teflon-lined stainless-steel bomb, which was then heated to 453 K for 100 h. The bomb was cooled to room temperature at 5 k h⁻¹. Block-shaped colorless crystals separated from the solution.

S3. Refinement

The diffraction measurements were of sufficiently high quality to allow for the refinement of the four H atoms, three of which lie on special positions, when restraints (O—H = 0.85±0.01 Å and C—H 0.93±0.01 Å) were applied.

Computing details

Data collection: SMART (Bruker, 2001); cell refinement: SMART; data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. ORTEPII (Johnson, 1976) plot of a fragment of the structure of the title compound at the 75% probability level. H atoms are drawn as spheres of arbitrary radii. [Symmetry codes: (i) 1/2 − x, 1/2 − y, −z; (ii) 1/2 − x, 1/2 + y, 1 − z.]
	Fig. 2. ORTEPII (Johnson, 1976) plot illustrating the hydroxyl–pyrazine–hydroxyl hydrogen bonds.
	Fig. 3. ORTEPII (Johnson, 1976) plot illustrating the geometry of the Na atom. [Symmetry codes: (i) 1/2 − x, 3/2 − y, 1 − z; (ii) x − 1/2, 3/2 − y, z; (iii) −x, y, 1 − z.]

Disodium bis(1,2,4,5-benzenetetracarboxylato)dihydroxytetrazincate(II)^.pyrazine

Crystal data

Na2[Zn4(C10H2O8)2(OH)2]·C4H4N2	F(000) = 908
Mr = 921.80	Dx = 2.312 Mg m^−3
Monoclinic, C2/m	Mo Kα radiation, λ = 0.71073 Å
a = 10.4073 (5) Å	Cell parameters from 5344 reflections
b = 17.8174 (8) Å	θ = 2.3–28.3°
c = 7.5278 (4) Å	µ = 3.71 mm^−1
β = 108.474 (1)°	T = 298 K
V = 1324.0 (1) Å^3	Block, colorless
Z = 2	0.29 × 0.17 × 0.12 mm

Data collection

Bruker APEX area-detector diffractometer	1629 independent reflections
Radiation source: fine-focus sealed tube	1470 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.035
ϕ and ω scans	θmax = 28.3°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −13→13
Tmin = 0.463, Tmax = 0.641	k = −23→23
7636 measured reflections	l = −9→9

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)] = 0.028	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.072	All H-atom parameters refined
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0429P)^2] where P = (Fo^2 + 2Fc^2)/3
1629 reflections	(Δ/σ)max = 0.001
130 parameters	Δρmax = 0.51 e Å^−3
4 restraints	Δρmin = −0.40 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Zn1	0.15965 (3)	0.72269 (1)	0.15033 (4)	0.0163 (1)
Na1	0.0000	0.75322 (8)	0.5000	0.0244 (3)
O1	0.3100 (2)	0.8655 (1)	−0.0101 (2)	0.0237 (4)
O2	0.3018 (2)	0.8000 (1)	0.2381 (2)	0.0178 (3)
O3	0.1603 (2)	0.8468 (1)	0.5297 (3)	0.0310 (4)
O4	0.3824 (2)	0.8303 (1)	0.6467 (2)	0.0197 (4)
O5	0.0000	0.7703 (1)	0.0000	0.0296 (6)
N1	0.0000	0.9230 (2)	0.0000	0.0398 (9)
C1	0.3293 (3)	1.0000	0.1793 (5)	0.0156 (6)
C2	0.3180 (2)	0.9321 (1)	0.2629 (3)	0.0140 (4)
C3	0.3013 (2)	0.9322 (1)	0.4399 (3)	0.0139 (4)
C4	0.2956 (3)	1.0000	0.5262 (4)	0.0167 (7)
C5	0.3108 (2)	0.8609 (1)	0.1562 (3)	0.0154 (4)
C6	0.2767 (2)	0.8633 (1)	0.5403 (3)	0.0171 (5)
C7	−0.0164 (3)	0.9616 (2)	0.1415 (5)	0.0390 (7)
H5	0.0000	0.8176 (6)	0.0000	0.03 (1)*
H1	0.339 (3)	1.0000	0.061 (2)	0.02 (1)*
H4	0.284 (4)	1.0000	0.644 (3)	0.03 (1)*
H7	−0.026 (3)	0.933 (2)	0.239 (3)	0.04 (1)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn1	0.0225 (2)	0.0114 (2)	0.0152 (2)	−0.0009 (1)	0.0064 (1)	0.0001 (1)
Na1	0.0209 (7)	0.0196 (7)	0.0354 (8)	0.000	0.0125 (6)	0.000
O1	0.043 (1)	0.013 (1)	0.018 (1)	0.002 (1)	0.013 (1)	−0.002 (1)
O2	0.023 (1)	0.011 (1)	0.017 (1)	−0.003 (1)	0.004 (1)	0.000 (1)
O3	0.026 (1)	0.023 (1)	0.048 (1)	−0.002 (1)	0.017 (1)	0.009 (1)
O4	0.027 (1)	0.016 (1)	0.017 (1)	0.004 (1)	0.009 (1)	0.005 (1)
O5	0.025 (1)	0.013 (1)	0.040 (2)	0.000	−0.006 (1)	0.000
N1	0.033 (2)	0.018 (2)	0.057 (2)	0.000	−0.003 (2)	0.000
C1	0.020 (2)	0.014 (2)	0.014 (2)	0.000	0.007 (1)	0.000
C2	0.016 (2)	0.011 (1)	0.014 (1)	0.000 (1)	0.004 (1)	−0.001 (1)
C3	0.014 (1)	0.012 (1)	0.016 (1)	0.000 (1)	0.004 (1)	0.002 (1)
C4	0.023 (2)	0.017 (2)	0.012 (2)	0.000	0.008 (1)	0.000
C5	0.016 (1)	0.012 (1)	0.017 (1)	0.000 (1)	0.005 (1)	−0.002 (1)
C6	0.027 (1)	0.012 (1)	0.015 (1)	−0.002 (1)	0.010 (1)	−0.002 (1)
C7	0.032 (2)	0.030 (2)	0.046 (2)	0.000 (1)	0.000 (1)	0.006 (1)

Geometric parameters (Å, º)

Zn1—O1^i	1.973 (2)	N1—C7^v	1.324 (4)
Zn1—O2	1.975 (2)	N1—C7	1.324 (4)
Zn1—O4^ii	1.960 (2)	C1—C2^vi	1.386 (3)
Zn1—O5	1.890 (1)	C1—C2	1.386 (3)
Na1—O2^ii	2.542 (2)	C2—C3	1.398 (3)
Na1—O2^iii	2.542 (2)	C2—C5	1.490 (3)
Na1—O3	2.319 (2)	C3—C4	1.382 (3)
Na1—O3^iv	2.319 (2)	C3—C6	1.505 (3)
Na1—O4^ii	2.406 (2)	C4—C3^vi	1.382 (3)
Na1—O4^iii	2.406 (2)	C7—C7^vi	1.370 (6)
O1—C5	1.252 (3)	O5—H5	0.84 (1)
O2—C5	1.266 (3)	C1—H1	0.93 (1)
O3—C6	1.224 (3)	C4—H4	0.93 (1)
O4—C6	1.279 (3)	C7—H7	0.93 (1)
O1^i—Zn1—O2	120.3 (1)	C6—O4—Na1^ii	117.3 (1)
O1^i—Zn1—O4^ii	98.5 (1)	Zn1^ii—O4—Na1^ii	109.4 (1)
O1^i—Zn1—O5	107.3 (1)	Zn1^v—O5—Zn1	126.6 (1)
O2—Zn1—O4^ii	113.8 (1)	C7^v—N1—C7	117.4 (4)
O2—Zn1—O5	108.1 (1)	C2^vi—C1—C2	121.7 (3)
O4^ii—Zn1—O5	108.2 (1)	C1—C2—C3	119.1 (2)
O2^ii—Na1—O2^iii	136.2 (1)	C1—C2—C5	119.7 (2)
O2^ii—Na1—O3	79.1 (1)	C3—C2—C5	121.0 (2)
O2^ii—Na1—O3^iv	136.5 (1)	C4—C3—C2	119.1 (2)
O2^ii—Na1—O4^ii	73.7 (1)	C4—C3—C6	116.0 (2)
O2^ii—Na1—O4^iii	79.6 (1)	C2—C3—C6	124.7 (2)
O2^iii—Na1—O3	136.5 (1)	C3—C4—C3^vi	121.9 (3)
O2^iii—Na1—O3^iv	79.1 (1)	O1—C5—O2	124.4 (2)
O2^iii—Na1—O4^ii	79.6 (1)	O1—C5—C2	117.8 (2)
O2^iii—Na1—O4^iii	73.7 (1)	O2—C5—C2	117.8 (2)
O3—Na1—O3^iv	88.1 (1)	O3—C6—O4	124.6 (2)
O3—Na1—O4^ii	91.9 (1)	O3—C6—C3	118.9 (2)
O3—Na1—O4^iii	148.8 (1)	O4—C6—C3	116.1 (2)
O3^iv—Na1—O4^ii	148.8 (1)	N1—C7—C7^vi	121.3 (2)
O3^iv—Na1—O4^iii	91.9 (1)	Zn1^v—O5—H5	116.7 (1)
O4^ii—Na1—O4^iii	103.6 (1)	Zn1—O5—H5	116.7 (1)
C5—O1—Zn1^i	122.1 (2)	C2^vi—C1—H1	119.1 (2)
C5—O2—Zn1	126.7 (2)	C2—C1—H1	119.1 (2)
C5—O2—Na1^ii	122.0 (1)	C3—C4—H4	119.0 (2)
Zn1—O2—Na1^ii	109.7 (1)	C3^vi—C4—H4	119 (3)
C6—O3—Na1	147.7 (2)	N1—C7—H7	115 (2)
C6—O4—Zn1^ii	110.5 (1)	C7^vi—C7—H7	124 (2)
O5—Zn1—O2—C5	−27.6 (2)	Zn1^i—O1—C5—O2	−15.7 (3)
O4^ii—Zn1—O2—C5	−147.8 (2)	Zn1^i—O1—C5—C2	166.5 (1)
O1^i—Zn1—O2—C5	96.0 (2)	Zn1—O2—C5—O1	−53.5 (3)
O5—Zn1—O2—Na1^ii	166.6 (1)	Na1^ii—O2—C5—O1	110.7 (2)
O4^ii—Zn1—O2—Na1^ii	46.5 (1)	Zn1—O2—C5—C2	124.3 (2)
O1^i—Zn1—O2—Na1^ii	−69.9 (1)	Na1^ii—O2—C5—C2	−71.5 (2)
O3^iv—Na1—O3—C6	−172.9 (4)	C1—C2—C5—O1	−2.7 (3)
O4^ii—Na1—O3—C6	−24.1 (3)	C3—C2—C5—O1	171.5 (2)
O4^iii—Na1—O3—C6	96.6 (3)	C1—C2—C5—O2	179.3 (2)
O2^iii—Na1—O3—C6	−101.0 (3)	C3—C2—C5—O2	−6.5 (3)
O2^ii—Na1—O3—C6	48.9 (3)	Na1—O3—C6—O4	−47.0 (5)
O4^ii—Zn1—O5—Zn1^v	−66.3 (1)	Na1—O3—C6—C3	140.4 (2)
O1^i—Zn1—O5—Zn1^v	39.0 (1)	Zn1^ii—O4—C6—O3	−20.4 (3)
O2—Zn1—O5—Zn1^v	170.1 (1)	Na1^ii—O4—C6—O3	105.8 (2)
C2^vi—C1—C2—C3	−3.1 (5)	Zn1^ii—O4—C6—C3	152.4 (2)
C2^vi—C1—C2—C5	171.2 (2)	Na1^ii—O4—C6—C3	−81.4 (2)
C1—C2—C3—C4	0.4 (4)	C4—C3—C6—O3	78.2 (3)
C5—C2—C3—C4	−173.8 (2)	C2—C3—C6—O3	−96.5 (3)
C1—C2—C3—C6	174.9 (2)	C4—C3—C6—O4	−95.1 (3)
C5—C2—C3—C6	0.7 (3)	C2—C3—C6—O4	90.3 (3)
C2—C3—C4—C3^vi	2.3 (5)	C7^v—N1—C7—C7^vi	0.0 (1)
C6—C3—C4—C3^vi	−172.7 (2)

Symmetry codes: (i) −x+1/2, −y+3/2, −z; (ii) −x+1/2, −y+3/2, −z+1; (iii) x−1/2, −y+3/2, z; (iv) −x, y, −z+1; (v) −x, y, −z; (vi) x, −y+2, z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5···N1	0.84 (1)	1.88 (1)	2.720 (4)	180 (?)