The layered structure of poly[[hexa­aqua­([mu]₄-benzene-1,2,4,5-tetra­car­box­yl­ato)dicopper(II)] tetra­hydrate]

In the structure of the title compound, {[Cu₂(C₁₀H₂O₈)(H₂O)₆]·4H₂O}_n, the benzene-1,2,4,5-tetra­carboxyl­ate ligand, (btec)^4-, is located on a crystallographic inversion centre in a [mu]₄-coordination mode. The coordination environment of each penta­coordinated Cu^II centre is square pyramidal (SBP), formed by three water mol­ecules and two carboxyl­ate O atoms from two different (btec)^4- ligands. The completely deprotonated (btec)^4- ligand coordinates in a monodentate mode to four Cu^II atoms. The alternation of (btec)^4- ligands and SBP Cu^II centres leads to the formation of a planar two-dimensional covalent network of parallelograms, parallel to the ab plane. Hydrogen bonds between a basal water mol­ecule and an apical one from an adjacent [Cu(btec)_0.5(H₂O)₃] unit exist in the intra­layer space. Hydrogen bonds are also present between the two-dimensional network and the water mol­ecules filling the channels in the structure.

Computing details

Data collection: APEX2 (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXTL (Bruker, 2001).

Poly[[hexaaqua(µ₄-benzene-1,2,4,5-tetracarboxylato)dicopper(II)] tetrahydrate]

Crystal data

[Cu2(C10H2O8)(H2O)6]·4H2O	F(000) = 1136
Mr = 278.68	Dx = 1.901 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 5027 reflections
a = 12.1571 (3) Å	θ = 3.2–26.1°
b = 18.1138 (4) Å	µ = 2.27 mm^−1
c = 9.6370 (4) Å	T = 296 K
β = 113.405 (1)°	Needle, blue
V = 1947.56 (10) Å^3	0.75 × 0.42 × 0.36 mm
Z = 8

Data collection

Bruker SMART APEXII area-detector diffractometer	1911 independent reflections
Radiation source: fine-focus sealed tube	1773 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.000
φ and ω scans	θmax = 26.0°, θmin = 2.6°
Absorption correction: empirical (using intensity measurements) (SADABS; Bruker, 2001)	h = −14→14
Tmin = 0.281, Tmax = 0.493	k = 0→22
4973 measured reflections	l = 0→11

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)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.083	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0333P)^2 + 2.2354P] where P = (Fo^2 + 2Fc^2)/3
1911 reflections	(Δ/σ)max = 0.001
142 parameters	Δρmax = 0.92 e Å^−3
6 restraints	Δρmin = −0.48 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.

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

- 8.2615 (0.0049) x + 11.0944 (0.0074) y + 6.1727 (0.0045) z = 6.7576 (0.0042)

* -0.0345 (0.0006) Cu * -0.0458 (0.0007) O1 * 0.0630 (0.0008) O6 * 0.0670 (0.0008) O5 * -0.0497 (0.0008) O3_$8

Rms deviation of fitted atoms = 0.0533

5.5927 (0.0102) x - 7.4133 (0.0147) y + 5.2077 (0.0074) z = 1.5270 (0.0108)

Angle to previous plane (with approximate e.s.d.) = 75.81 (0.06)

* -0.0041 (0.0005) O1 * 0.0115 (0.0014) C1 * -0.0033 (0.0004) C2 * -0.0041 (0.0005) O2

Rms deviation of fitted atoms = 0.0066 the 7.3951 (0.0096) x - 7.9113 (0.0178) y + 3.5326 (0.0095) z = 0.8877 (0.0105)

Angle to previous plane (with approximate e.s.d.) = 65.59 (0.06)

* 0.0021 (0.0006) O3_$8 * -0.0058 (0.0016) C5_$8 * 0.0016 (0.0004) C4_$8 * 0.0022 (0.0006) O4_$8

Rms deviation of fitted atoms = 0.0034

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
Cu1	0.27996 (2)	0.441393 (15)	0.67052 (3)	0.01200 (13)
O1	0.37365 (16)	0.52682 (9)	0.64069 (19)	0.0148 (4)
C1	0.3665 (2)	0.57872 (13)	0.7256 (3)	0.0111 (5)
O2	0.29745 (17)	0.57583 (10)	0.7923 (2)	0.0195 (4)
C2	0.4398 (2)	0.64728 (13)	0.7414 (3)	0.0102 (5)
C3	0.3825 (2)	0.71442 (13)	0.7360 (3)	0.0132 (5)
H5A	0.3036	0.7145	0.7276	0.016*
C4	0.4407 (2)	0.78137 (13)	0.7429 (3)	0.0125 (5)
C5	0.3723 (2)	0.85229 (13)	0.7288 (3)	0.0148 (5)
O3	0.32031 (17)	0.85931 (10)	0.8187 (2)	0.0207 (4)
O4	0.3696 (2)	0.89728 (12)	0.6308 (3)	0.0337 (5)
O5	0.15185 (18)	0.46427 (11)	0.4747 (2)	0.0250 (4)
H1W	0.157 (4)	0.5056 (15)	0.431 (5)	0.073 (15)*
H2W	0.082 (2)	0.445 (3)	0.454 (6)	0.082 (19)*
O6	0.39550 (18)	0.42212 (13)	0.8757 (2)	0.0251 (4)
H3W	0.392 (5)	0.450 (2)	0.948 (4)	0.076 (17)*
H4W	0.4656 (19)	0.402 (2)	0.900 (5)	0.062 (14)*
O7	0.38393 (17)	0.37018 (11)	0.5742 (2)	0.0201 (4)
H5W	0.346 (4)	0.370 (3)	0.4764 (7)	0.080 (17)*
H6W	0.383 (3)	0.3226 (3)	0.586 (4)	0.031 (9)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.01281 (19)	0.00741 (18)	0.01753 (19)	−0.00314 (10)	0.00786 (13)	0.00076 (10)
O1	0.0199 (9)	0.0082 (8)	0.0188 (9)	−0.0044 (7)	0.0103 (7)	−0.0026 (7)
C1	0.0095 (11)	0.0085 (11)	0.0146 (11)	0.0005 (9)	0.0041 (9)	0.0022 (9)
O2	0.0205 (9)	0.0157 (9)	0.0294 (10)	−0.0050 (7)	0.0175 (8)	−0.0030 (8)
C2	0.0122 (11)	0.0058 (11)	0.0142 (11)	−0.0008 (9)	0.0069 (9)	−0.0001 (8)
C3	0.0109 (10)	0.0093 (12)	0.0211 (12)	0.0007 (9)	0.0083 (10)	0.0021 (9)
C4	0.0155 (12)	0.0077 (11)	0.0183 (11)	0.0019 (9)	0.0110 (10)	0.0008 (9)
C5	0.0142 (11)	0.0072 (11)	0.0237 (12)	0.0000 (9)	0.0081 (10)	−0.0006 (9)
O3	0.0261 (10)	0.0142 (9)	0.0281 (10)	0.0096 (8)	0.0174 (8)	0.0020 (8)
O4	0.0447 (13)	0.0188 (11)	0.0524 (14)	0.0142 (9)	0.0350 (12)	0.0191 (10)
O5	0.0183 (10)	0.0176 (10)	0.0314 (11)	−0.0040 (8)	0.0019 (8)	0.0087 (9)
O6	0.0225 (10)	0.0347 (12)	0.0196 (10)	0.0081 (9)	0.0100 (8)	0.0022 (9)
O7	0.0232 (10)	0.0158 (10)	0.0233 (10)	0.0000 (8)	0.0113 (8)	−0.0013 (8)

Geometric parameters (Å, º)

Cu1—O6	1.949 (2)	C3—C4	1.392 (3)
Cu1—O3^i	1.9513 (18)	C3—H5A	0.9300
Cu1—O5	1.956 (2)	C4—C4^iii	1.393 (5)
Cu1—O1	2.0087 (17)	C4—C5	1.507 (3)
Cu1—O7	2.248 (2)	C5—O4	1.238 (3)
O3—Cu1^ii	1.9513 (18)	C5—O3	1.266 (3)
Cu1—Cu1^i	9.2625 (5)	O5—H1W	0.8700
O1—C1	1.272 (3)	O5—H2W	0.8700
C1—O2	1.244 (3)	O6—H3W	0.8700
C1—C2	1.501 (3)	O6—H4W	0.8700
C2—C3	1.392 (3)	O7—H5W	0.8700
C2—C2^iii	1.406 (5)	O7—H6W	0.8700
O6—Cu1—O3^i	91.34 (9)	C2—C3—H5A	119.3
O6—Cu1—O5	173.67 (9)	C4—C3—H5A	119.3
O3^i—Cu1—O5	86.44 (8)	C3—C4—C4^iii	119.42 (14)
O6—Cu1—O1	93.56 (9)	C3—C4—C5	119.1 (2)
O3^i—Cu1—O1	175.08 (8)	C4^iii—C4—C5	121.43 (13)
O5—Cu1—O1	88.74 (8)	O4—C5—O3	126.0 (2)
O6—Cu1—O7	91.10 (8)	O4—C5—C4	118.4 (2)
O3^i—Cu1—O7	92.88 (8)	O3—C5—C4	115.5 (2)
O5—Cu1—O7	94.93 (8)	C5—O3—Cu1^ii	127.24 (17)
O1—Cu1—O7	86.52 (7)	Cu1—O5—H1W	118
C1—O1—Cu1	106.82 (15)	Cu1—O5—H2W	118
O2—C1—O1	122.3 (2)	H1W—O5—H2W	119
O2—C1—C2	118.6 (2)	Cu1—O6—H3W	118
O1—C1—C2	119.1 (2)	Cu1—O6—H4W	125
C3—C2—C2^iii	119.11 (14)	H3W—O6—H4W	112
C3—C2—C1	116.8 (2)	Cu1—O7—H5W	108
C2^iii—C2—C1	124.10 (13)	Cu1—O7—H6W	118
C2—C3—C4	121.4 (2)	H5W—O7—H6W	97
O6—Cu1—O1—C1	−69.63 (16)	C2^iii—C2—C3—C4	1.9 (4)
O3^i—Cu1—O1—C1	116.5 (9)	C1—C2—C3—C4	−177.2 (2)
O5—Cu1—O1—C1	104.47 (16)	C2—C3—C4—C4^iii	−0.6 (4)
O7—Cu1—O1—C1	−160.52 (16)	C2—C3—C4—C5	176.9 (2)
Cu1—O1—C1—O2	−9.6 (3)	C3—C4—C5—O4	−125.5 (3)
Cu1—O1—C1—C2	173.00 (16)	C4^iii—C4—C5—O4	52.0 (4)
O2—C1—C2—C3	−41.2 (3)	C3—C4—C5—O3	53.2 (3)
O1—C1—C2—C3	136.3 (2)	C4^iii—C4—C5—O3	−129.2 (3)
O2—C1—C2—C2^iii	139.7 (3)	O4—C5—O3—Cu1^ii	0.7 (4)
O1—C1—C2—C2^iii	−42.8 (4)	C4—C5—O3—Cu1^ii	−177.94 (16)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O6—H4W···O7^iii	0.87	1.84	2.698 (3)	170
O5—H1W···O4^iv	0.87	1.85	2.679 (3)	160
O7—H5W···O2^v	0.87	1.90	2.679 (3)	148
O6—H3W···O1^vi	0.87	2.00	2.826 (3)	157

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