Poly[tetraaqua­(μ₆-benzene-1,2,4,5-tetra­carboxyl­ato)dicopper(II)]

The title compound, [Cu₂(C₁₀H₂O₈)(H₂O)₄]_n, is isostructural with the analogous Zn polymeric compound [Wang, Lu, Yang, Zhao & Ng (2007). Acta Cryst. E63, m2986]. Each Cu^II ion is coordinated by five O atoms [Cu—O = 1.968 (2)–2.268 (3) Å] in a trigonal–bipyramidal geometry. The coordinating water mol­ecules are involved in inter­molecular O—H...O hydrogen bonds [O...O = 2.726 (3)–2.767 (3) Å], which consolidate the packing.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.046
• wR factor = 0.112
• Data-to-parameter ratio = 9.9

checkCIF/PLATON results

No syntax errors found



Alert level C
RINTA01_ALERT_3_C  The value of Rint is greater than 0.10
            Rint given   0.107
PLAT020_ALERT_3_C The value of Rint is greater than 0.10 .........       0.11
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.96
PLAT088_ALERT_3_C Poor Data / Parameter Ratio ....................       9.93
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.91 Ratio
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Cu1    -   O3      ..       9.78 su
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........          4
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.13 Ratio

Alert level G
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          6

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

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

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S1. Comment

A zinc compound with 1,2,4,5-benzenetetracarboxylate was reported recently (Wang et al., 2007). A slight variation of the synthesis has yielded the title compound, which features trigonal-bipyramidal copper coordination environment.

Related literature

The crystal structure of the analogous Zn comphas been reported by Wang et al. (2007).

S2. Experimental

Benzenetetracarboxylic acid (0.023 g, 0.015 mmol), CuCl2 (0.018 g, 0.013 mmol) and NaOH(0.048 mmol,0.12 mmol), were added in a mixed solvent of ethanol, the mixture was heated for ten hours under reflux, applying stirring and influx. The resultant was then filtered to give a pure solution which was infiltrated by diethyl ether freely in a closed vessel. Two weeks later several single crystals of the size suitable for X-Ray diffraction analysis were obtained.

S3. Refinement

C-bound H atoms were placed in calculated positions [Csp²—H = 0.93 Å] and refined using a riding model, with U_iso(H) = 1.2U_eq(C). The water' H atoms were found in a difference map and isotropically refined using bond restraint O—H = 0.86 (3) Å.

Computing details

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2004); software used to prepare material for publication: SHELXTL.

Poly[tetraaqua(µ₆-benzene-1,2,4,5-tetracarboxylato)dicopper(II)]

Crystal data

[Cu2(C10H2O8)(H2O)4]	F(000) = 448
Mr = 224.63	Dx = 2.153 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1261 reflections
a = 5.2594 (10) Å	θ = 2.5–25.3°
b = 16.342 (3) Å	µ = 3.14 mm^−1
c = 8.1426 (15) Å	T = 298 K
β = 97.939 (2)°	Block, blue
V = 693.1 (2) Å^3	0.28 × 0.19 × 0.15 mm
Z = 4

Data collection

Bruker APEXII area-detector diffractometer	1261 independent reflections
Radiation source: fine-focus sealed tube	1181 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.107
ϕ and ω scan	θmax = 25.3°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	h = −6→5
Tmin = 0.474, Tmax = 0.651	k = −19→16
3586 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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.112	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0794P)^2 + 0.002P] where P = (Fo^2 + 2Fc^2)/3
1261 reflections	(Δ/σ)max = 0.001
127 parameters	Δρmax = 0.77 e Å^−3
6 restraints	Δρmin = −1.63 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
O1	0.6295 (4)	0.78499 (13)	1.0770 (3)	0.0251 (5)
O5	0.9211 (4)	0.87035 (13)	0.7881 (3)	0.0234 (5)
C4	0.8535 (5)	0.94425 (18)	0.7784 (4)	0.0185 (7)
Cu1	0.14625 (6)	0.83280 (2)	0.62933 (4)	0.0155 (3)
O2	0.4254 (4)	0.79262 (13)	0.8192 (2)	0.0224 (5)
O6	0.9316 (4)	0.99467 (13)	0.6821 (3)	0.0263 (6)
O3	−0.1623 (5)	0.86478 (15)	0.4160 (3)	0.0262 (6)
C1	0.5292 (6)	0.82451 (18)	0.9505 (4)	0.0181 (7)
O4	0.3800 (4)	0.90417 (15)	0.5221 (3)	0.0307 (6)
C5	0.6389 (6)	1.05457 (18)	0.9193 (4)	0.0192 (7)
H13	0.7321	1.0916	0.8645	0.023*
C2	0.5243 (6)	0.91568 (18)	0.9736 (3)	0.0164 (6)
C3	0.6668 (5)	0.97141 (18)	0.8918 (3)	0.0174 (6)
H3WA	−0.120 (9)	0.9099 (15)	0.372 (5)	0.061 (16)*
H4WA	0.293 (6)	0.938 (2)	0.455 (4)	0.041 (12)*
H4WB	0.515 (6)	0.888 (3)	0.482 (5)	0.062 (15)*
H3WB	−0.175 (12)	0.825 (2)	0.346 (5)	0.09 (3)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0368 (14)	0.0178 (11)	0.0196 (11)	−0.0001 (9)	0.0002 (9)	0.0012 (9)
O5	0.0260 (12)	0.0217 (12)	0.0254 (11)	0.0056 (9)	0.0136 (9)	0.0008 (9)
C4	0.0162 (15)	0.0232 (17)	0.0174 (15)	−0.0011 (12)	0.0071 (12)	−0.0013 (12)
Cu1	0.0164 (3)	0.0160 (4)	0.0162 (4)	0.00117 (12)	0.0090 (2)	−0.00035 (12)
O2	0.0250 (12)	0.0207 (12)	0.0210 (11)	0.0012 (9)	0.0017 (9)	−0.0021 (9)
O6	0.0290 (12)	0.0264 (11)	0.0275 (13)	0.0011 (9)	0.0182 (10)	0.0047 (10)
O3	0.0278 (13)	0.0260 (13)	0.0268 (12)	−0.0019 (11)	0.0111 (9)	−0.0018 (11)
C1	0.0154 (16)	0.0213 (16)	0.0193 (18)	0.0006 (11)	0.0088 (13)	0.0004 (12)
O4	0.0217 (13)	0.0379 (14)	0.0352 (14)	0.0044 (10)	0.0134 (11)	0.0143 (11)
C5	0.0200 (15)	0.0222 (16)	0.0168 (15)	−0.0022 (12)	0.0078 (11)	0.0018 (12)
C2	0.0164 (15)	0.0190 (14)	0.0142 (14)	0.0018 (11)	0.0032 (11)	−0.0003 (12)
C3	0.0192 (15)	0.0206 (15)	0.0136 (15)	0.0020 (12)	0.0060 (11)	−0.0002 (12)

Geometric parameters (Å, º)

O1—C1	1.267 (4)	O2—C1	1.246 (4)
O1—Cu1^i	1.971 (2)	O3—H3WA	0.86 (3)
O5—C4	1.258 (4)	O3—H3WB	0.86 (4)
O5—Cu1^ii	1.968 (2)	C1—C2	1.502 (4)
C4—O6	1.245 (3)	O4—H4WA	0.86 (3)
C4—C3	1.504 (4)	O4—H4WB	0.86 (3)
Cu1—O5^iii	1.968 (2)	C5—C3	1.388 (4)
Cu1—O1^iv	1.971 (2)	C5—C2^v	1.393 (4)
Cu1—O4	1.983 (2)	C5—H13	0.9300
Cu1—O2	2.086 (2)	C2—C5^v	1.393 (4)
Cu1—O3	2.268 (3)	C2—C3	1.405 (4)
C1—O1—Cu1^i	132.4 (2)	Cu1—O3—H3WB	108 (4)
C4—O5—Cu1^ii	116.65 (19)	H3WA—O3—H3WB	112 (3)
O6—C4—O5	124.0 (3)	O2—C1—O1	124.6 (3)
O6—C4—C3	119.4 (3)	O2—C1—C2	120.6 (3)
O5—C4—C3	116.6 (3)	O1—C1—C2	114.6 (3)
O5^iii—Cu1—O1^iv	115.69 (9)	Cu1—O4—H4WA	110 (3)
O5^iii—Cu1—O4	124.88 (9)	Cu1—O4—H4WB	125 (3)
O1^iv—Cu1—O4	119.42 (10)	H4WA—O4—H4WB	111 (2)
O5^iii—Cu1—O2	92.13 (9)	C3—C5—C2^v	122.0 (3)
O1^iv—Cu1—O2	81.88 (9)	C3—C5—H13	119.0
O4—Cu1—O2	95.50 (10)	C2^v—C5—H13	119.0
O5^iii—Cu1—O3	89.96 (9)	C5^v—C2—C3	119.1 (3)
O1^iv—Cu1—O3	93.08 (9)	C5^v—C2—C1	116.5 (3)
O4—Cu1—O3	87.06 (10)	C3—C2—C1	124.4 (3)
O2—Cu1—O3	174.95 (8)	C5—C3—C2	118.9 (3)
C1—O2—Cu1	133.2 (2)	C5—C3—C4	118.7 (3)
Cu1—O3—H3WA	108 (3)	C2—C3—C4	122.4 (3)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3WA···O6^vi	0.86 (3)	1.93 (2)	2.767 (3)	163 (5)
O3—H3WB···O1^vii	0.86 (4)	2.38 (4)	3.112 (3)	143 (5)
O3—H3WB···O2^iv	0.86 (4)	2.01 (4)	2.748 (3)	143 (5)
O4—H4WA···O6^vi	0.86 (3)	1.87 (3)	2.726 (3)	173 (4)
O4—H4WB···O3^ii	0.86 (3)	1.89 (3)	2.744 (3)	171 (5)

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