Copper(II) succinate complexes with 1,2-di-4-pyridylethane and 1,3-di-4-pyridylpropane

The compounds poly[di-μ₄-succinato-μ₂-1,2-di-4-pyridyl­eth­ane-dicopper(II)], [Cu₂(C₄H₄O₄)₂(C₁₂H₁₂N₂)]_n, (I), and poly[di-μ₄-succinato-μ₂-1,3-di-4-pyridylpropane-dicopper(II)], [Cu₂(C₄H₄O₄)₂(C₁₃H₁₄N₂)]_n, (II), exhibit polymeric structures with the dicopper units doubly bridged by bis-bidentate succinate groups and crosslinked by the separator bis­(pyridyl) mol­ecules. In (I), the mol­ecule exhibits a centre of inversion located midway between the core Cu-dimer atoms and another that relates half of the bis­(pyridyl)ethane ligand to the other half. Compound (II) has a similar mol­ecular packing but with a doubled lattice constant and noncentrosymmetric core units. An anti­ferromagnetic inter­action due to the dinuclear copper units was deduced from magnetic subsceptibility measurements, and spin triplet signals were detected in the electron paramagnetic resonance spectra for both compounds.

S1. Comment

Metal–organic coordination polymers are of great current interest and spacer ligands are frequently used to form new extended framework structures. Dimetal units can be combined with the bidentate organic ligands 1,2-di-4-pyridylethane and 1,3-di-4-pyridylpropane as flexible organic spacers to give rise to a large variety of structures (Batsanov et al., 1996; Suen et al., 2006; Carballo et al., 2007). The resultant structures combining dimetal units of Cu₂(OAc)₄ with two different N,N'-bidentate ligands, 1,2-di-4-pyridylethane and 1,4-di-4-pyridylbuta-1,3-diyne, have been reported as one-dimensional polymer chains containing a bridging nitrogenated ligand and Cu₂(OAc)₄ dimeric units (Goforth et al., 2005). Besides the observed polymorphism due to the crystallization conditions, π–π interactions between the pyridyl rings play an important role in the resultant packing of the polymeric chains (Hu et al., 2005).

During investigations of the magnetic properties of compounds based on copper(II) succinate complexes, two new compounds were synthesized with 1,2-di-4-pyridylethane and 1,3-di-4-pyridylpropane as bidentate ligands. Our goal was centred on the structural frameworks resulting from the interaction of the succinate chains with N,N'-bidentate spacer ligands. The structure of the binuclear unit was reported by O'Connor & Maslen (1966) for the copper succinate dihydrate, [Cu(C₄H₄O₄)].2H₂O. In that structure, ribbon-like chains of paddle-wheel dicopper units are doubly bridged through bis-bidentate succinate groups. Each succinate anion links two dimeric units in the chain and two linking succinate anions are located between each pair of dimeric copper groups. A water molecule is coordinated to each Cu atom in the apical position.

We have now synthesized two new compounds, (I) and (II), with 1,2-di-4-pyridylethane and 1,3-di-4-pyridylpropane as spacer ligands, respectively, and present their crystal structures here.

The structures of both compounds (I) and (II) can be described as ribbon-like chains of paddle-wheel dicopper units doubly bridged through bis-bidentate succinate groups in gauche conformations, with torsion angles C7—C8—C9—C10 = -67.6 (2)° in (I), and C1—C2—C3—C4 = 70.6 (6)° and C5—C6—C7—C8 = -62.47 (1)° in (II), similar to those found for [Cu(C₄H₄O₄)].2H₂O (O'Connor & Maslen, 1966). The molecular conformations are shown in Fig. 1 and the molecular packing, viewed along the [010] direction, in Fig. 2. The dimeric copper(II) units are coordinated through the two N atoms to the bidentate ligands in infinite chains. The –Cu–Cu–py(CH₂)_npy–Cu–Cu– chains run along the [101] direction in (I) and along the [201] direction in (II). The ligand molecules link the succinate chains to form two-dimensional sheets. In compound (I), the planes of successive pyridyl rings joined by the ethylene group are parallel. The pyridyl rings of parallel chains are symmetry-related by the twofold screw axis, and those at (x, y, z) and (1 - x, -1/2 + y, 3/2 - z) form a dihedral angle of 27.7 (3)° with a relative disposition far from eclipsed because of the shift of 1/2 b (the Cg···Cg distance between their centroids is 4.78 Å).

In compound (II), the pyridyl rings containing atoms N1 and N2 form a dihedral angle of 12.3 (3)° and exhibit two different interactions with the rings of parallel symmetry-related chains. For pairs of rings containing N1 at (x, y, z) and (2 - x, 1 - y, 1 - z), the Cg···Cg distance is 3.761 (3) Å (slip distance 1.29 Å), whereas for the rings containing N2 at (x, y, z) and (1 - x, 1 - y, 1 - z), these values are 3.631 (4) Å and 1.03 Å, respectively, which corresponds to a π–π interaction. In this way, the chains interact through these π–π stacking interactions between pyridyl ring pairs and a three-dimensional architecture is thereby established. Other such π–π interactions between pairs of aromatic rings have been described (Perlepes et al., 1992).

In both compounds, each Cu^II atom exhibits the same coordination, a square-pyramidal geometry. The geometry of the dinuclear unit is described in Tables 1 and 2 for compounds (I) and (II), respectively. The equatorial plane is formed by four O atoms of four succinate groups. The apical position is occupied by an N atom of a spacer ligand. The trigonality indices (Addison et al., 1984) deduced from the angle data [τ = 0.004 for (I), and 0.005 (Cu1) and 0.004 (Cu2) for (II)] indicate a square-pyramidal geometry. The Cu^II atoms are displaced from the basal plane toward the apical N atom by 0.218 Å in (I), and by 0.195 (Cu1) and 0.213 Å (Cu2) in (II). This coordination geometry is similar to that found for Cu^II succinate dihydrate (O'Connor & Maslen, 1966). The magnetic and electron paramgnetic resonance (EPR) results for [Cu(C₄H₄O₄)].2H₂O (Sharrok & Melnik, 1985) correspond to the antiferromagnetic interaction characteristic of dimeric units with four syn–syn bridging carboxylate groups. In compounds (I) and (II) we found similar results.

The magnetic and EPR results agree with those found for compounds containing a dimeric copper unit (Seco et al., 2002; Sapiña et al., 1994). The dominant magnetic interaction is the antiferromagnetism due to the presence of the dimeric units. A hypothetical interaction through the nitrogenated ligands is negligible, as was found for one-dimensional chains with 1,2-di-4-pyridylethane (Carballo et al., 2007).

S2. Experimental

A combined solution of (CuSO₄).5H₂O (0.125 mmol, 31 mg) and succinic acid (0.125 mmol, 15 mg) in H₂O (25 ml), 1,2-di-4-pyridylethane (0.125 mmol, 23 mg) in H₂O (25 ml) and urea (0.437 mmol, 26 mg) in H₂O (25 ml) was prepared. After approximately a month, small green crystals of (I) were obtained, suitable for X-ray crystallographic study. By the same procedure with 1,3-di-4-pyridylpropane, crystals of compound (II) were also obtained.

Temperature-dependent magnetic susceptibility data were collected in the 6.5–300 K range using a Quantum Design PPMS 6000 magnetometer in a field of 5 kOe. The χ_m.T values decrease with decreasing temperature in the manner characteristic of paddle-wheel dinuclear copper groups. The observed χ_m.T data were fitted to the Bleaney–Bowers equation for a dimer with S₁ = S₂ = 1/2, modified by the inclusion of a fraction of monomeric impurity (O'Connor, 1982): χ_m(2Cu) = 2{[Ce^x(1-ρ)/(1 + 3 e^x)] + Cρ/4 + Nα}, where C = Ng²β²/kT, x = 2 J/kT, 2 J = separation between singlet and triplet states, [T is the temperature, k is the Boltzmann constant?], ρ = fraction of monomeric impurity and Nα is the temperature-independent paramagnetism (TIP). The antiferromagnetic parameters are 2 J = -366 and -336 cm^-1 for (I) and (II), respectively. The powder EPR spectra of (I) and (II), recorded on a Bruker ESP 300 spectrometer at Q band and room temperature, show the five signals of the triplet state (S = 1) for D ≠ 0 and E ≈ 0. The spectra were interpreted according to the Wasserman, Snyder and Yager equations (Bencini & Gatteschi, 1990). The values g_parallel = 2.26/2.26, g_{perpendicular} = 2.07/2.06 and D = 0.36/0.37 cm^-1 for (I)/(II) were thereby obtained.

S3. Refinement

The space group for both compounds (I) and (II) is P2₁/c but the lattice constants cannot be compared directly. The relation between the cell parameters is given by a_I = 1/2c_II, b_I = b_II and c_I = a_II + 1/2c_II. The diffraction pattern of (II) shows a pseudo body-centred symmetry (h + k + l = 2n) which, combined with the genuine conditions for P2₁/c, gives pseudo-conditions for I2/a (standard C2/c).

For both compounds, the H-atom coordinates were calculated with C—H = 0.98 Å and constrained, with U_iso(H) = 1.2U_eq(C). The atomic displacement parameters of the pyridyl rings indicate some orientational disorder, with a large component of the thermal ellipsoid perpendicular to the plane of the ring.

Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2007) for (I); X-AREA (Stoe & Cie, 2006) for (II). Cell refinement: CrysAlis RED (Oxford Diffraction, 2007) for (I); X-AREA (Stoe & Cie, 2006) for (II). Data reduction: CrysAlis RED (Oxford Diffraction, 2007) for (I); X-RED32 (Stoe & Cie, 2006) for (II). For both compounds, program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: JANA2006 (Petříček et al., 2006); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: JANA2006 (Petříček et al., 2006).

Figures

	Fig. 1. (a) A view of the copper coordination with a partial chain for (I) and (b) the configuration for compound (II). Atoms of the asymmetric units are labelled. For (I), the Cu—Cu vector is centred at (0, 1, 1/2). Displacement ellipsoids are drawn at the ??% probability level [Please complete] and H atoms are shown as small spheres of arbitrary radii.
	Fig. 2. Projections along [010], showing the molecular packing of (a) (I) and (b) (II).

(I) poly[di-µ₄-succinato-µ₂-1,2-di-4-pyridylethane-dicopper(II)]

Crystal data

[Cu2(C4H4O4)2(C12H12N2)]	F(000) = 552
Mr = 271.7	Dx = 1.803 (1) Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 852 reflections
a = 11.342 (2) Å	θ = 2.7–32.5°
b = 6.4613 (10) Å	µ = 2.18 mm^−1
c = 15.269 (4) Å	T = 295 K
β = 116.55 (3)°	Plate, green
V = 1000.9 (4) Å^3	0.16 × 0.16 × 0.02 mm
Z = 4

Data collection

Make? Model? CCD diffractometer	2885 independent reflections
Radiation source: X-ray tube	1225 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.093
Detector resolution: 8.3504 pixels mm^-1	θmax = 30.0°, θmin = 2.8°
ω–scans	h = −15→15
Absorption correction: integration (JANA2006; Petříček et al., 2006)	k = −9→9
Tmin = 0.763, Tmax = 0.960	l = −19→21
10503 measured reflections

Refinement

Refinement on F	0 constraints
R[F^2 > 2σ(F^2)] = 0.058	H-atom parameters constrained
wR(F^2) = 0.068	Weighting scheme based on measured s.u.'s w = 1/(σ^2(F) + 0.0004F^2)
S = 0.99	(Δ/σ)max = 0.050
2885 reflections	Δρmax = 1.83 e Å^−3
145 parameters	Δρmin = −0.97 e Å^−3
0 restraints

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

	x	y	z	Uiso*/Ueq
Cu1	0.11891 (8)	0.96724 (10)	0.57384 (4)	0.0306 (3)
O1	0.1287 (5)	0.7716 (6)	0.4796 (3)	0.044 (2)
O2	−0.0709 (4)	0.8189 (6)	0.3561 (2)	0.038 (2)
O4	0.1921 (5)	0.1807 (6)	0.5215 (2)	0.041 (2)
O3	−0.0079 (5)	0.2322 (6)	0.3975 (2)	0.040 (2)
N	0.2913 (5)	0.8234 (7)	0.6964 (3)	0.037 (3)
C1	0.2759 (5)	0.6208 (5)	0.7079 (3)	0.046 (4)
C2	0.3480 (5)	0.5129 (7)	0.7918 (3)	0.051 (4)
C3	0.4470 (4)	0.6124 (4)	0.8707 (4)	0.056 (4)
C4	0.4674 (5)	0.8205 (6)	0.8593 (3)	0.058 (4)
C5	0.3884 (5)	0.9144 (7)	0.7723 (3)	0.047 (4)
C6	0.5272 (4)	0.4949 (6)	0.9653 (2)	0.077 (3)
C7	0.03924 (9)	0.73493 (5)	0.39513 (6)	0.030 (3)
C8	0.0729 (4)	0.5824 (6)	0.33461 (19)	0.038 (3)
C9	0.16814 (9)	0.41667 (5)	0.39428 (4)	0.040 (3)
C10	0.11519 (9)	0.26539 (8)	0.443045 (7)	0.035 (4)
H1	0.208593	0.545486	0.652312	0.0549*
H2	0.329897	0.365936	0.796254	0.0617*
H4	0.536943	0.898338	0.912351	0.0693*
H5	0.404963	1.060965	0.765436	0.0565*
H6A	0.53552	0.34987	0.950241	0.0927*
H6B	0.617697	0.547881	0.996004	0.0927*
H8A	−0.008101	0.517982	0.285867	0.0456*
H8B	0.109137	0.656966	0.296179	0.0456*
H9A	0.19944	0.34115	0.35304	0.0481*
H9B	0.24855	0.48112	0.44380	0.0481*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0350 (5)	0.0290 (4)	0.0260 (3)	0.0021 (4)	0.0119 (3)	0.0028 (3)
O1	0.053 (4)	0.040 (2)	0.035 (2)	0.008 (2)	0.016 (2)	−0.0031 (18)
O2	0.049 (4)	0.034 (2)	0.033 (2)	−0.001 (2)	0.020 (2)	−0.0051 (16)
O4	0.040 (4)	0.040 (3)	0.041 (2)	0.001 (2)	0.018 (2)	0.0073 (17)
O3	0.043 (4)	0.034 (2)	0.041 (2)	0.013 (2)	0.016 (3)	0.0118 (17)
N	0.044 (5)	0.032 (3)	0.032 (2)	0.005 (3)	0.013 (3)	0.006 (2)
C1	0.036 (6)	0.042 (4)	0.047 (3)	0.013 (4)	0.008 (4)	0.000 (3)
C2	0.045 (7)	0.035 (4)	0.071 (4)	0.009 (4)	0.024 (4)	0.021 (3)
C3	0.038 (6)	0.087 (5)	0.048 (4)	0.019 (5)	0.024 (4)	0.029 (4)
C4	0.050 (7)	0.074 (5)	0.032 (3)	0.000 (5)	0.003 (4)	0.006 (3)
C5	0.044 (6)	0.047 (4)	0.049 (3)	−0.001 (4)	0.019 (4)	0.001 (3)
C6	0.055 (5)	0.120 (3)	0.053 (3)	0.021 (3)	0.020 (3)	0.045 (2)
C7	0.047 (5)	0.014 (4)	0.033 (3)	0.008 (3)	0.020 (3)	0.008 (2)
C8	0.057 (5)	0.035 (3)	0.031 (3)	0.004 (3)	0.028 (4)	0.005 (2)
C9	0.051 (5)	0.040 (4)	0.041 (3)	0.002 (3)	0.031 (3)	−0.002 (3)
C10	0.036 (6)	0.029 (7)	0.047 (4)	0.016 (6)	0.025 (4)	−0.004 (4)

Geometric parameters (Å, º)

Cu1—Cu1^i	2.665 (2)	C2—H2	0.980
Cu1—O1	1.955 (4)	C3—C4	1.388 (5)
Cu1—O2^i	1.967 (4)	C3—C6	1.522 (5)
Cu1—O4^ii	1.955 (5)	C4—C5	1.368 (6)
Cu1—O3^iii	1.983 (5)	C4—H4	0.980
Cu1—N	2.218 (4)	C5—H5	0.980
O1—C7	1.257 (3)	C6—C6^iv	1.445 (7)
O2—C7	1.243 (4)	C6—H6A	0.980
O4—C10	1.250 (3)	C6—H6B	0.980
O3—C10	1.269 (5)	C7—C8	1.512 (4)
N—C1	1.342 (6)	C8—C9	1.504 (4)
N—C5	1.327 (6)	C8—H8A	0.980
C1—C2	1.364 (6)	C8—H8B	0.980
C1—H1	0.980	C9—C10	1.5067 (11)
C2—C3	1.384 (5)
O1—Cu1—O2^i	167.08 (15)	C2—C1—H1	118.0
O1—Cu1—O4^ii	88.93 (19)	C1—C2—H2	120.0
O1—Cu1—O3^iii	89.57 (19)	C3—C2—H2	120.0
O2^i—Cu1—O4^ii	89.86 (19)	C3—C4—H4	121.0
O2^i—Cu1—O3^iii	88.83 (19)	C5—C4—H4	121.0
O4^ii—Cu1—O3^iii	167.50 (15)	C4—C5—H5	117.0
O1—C7—O2	125.9 (3)	C7—C8—C9	113.75 (18)
O4—C10—O3	125.2 (3)	C7—C8—H8A	109.0
C1—N—C5	115.1 (4)	C7—C8—H8B	109.0
C1—C2—C3	119.5 (4)	C10—C9—H9A	109.0
C2—C3—C4	117.2 (4)	C10—C9—H9B	109.0
C2—C3—C6	120.2 (3)	C8—C9—H9A	109.0
C4—C3—C6	122.7 (3)	C8—C9—H9B	109.0
C3—C4—C5	118.6 (4)	C3—C6—C6^iv	113.8 (2)
C7—C8—C9	113.75 (18)	C3—C6—H6A	109.0
C8—C9—C10	115.1 (2)	C3—C6—H6B	109.0
C3—C6—C6^iv	113.8 (4)	C6^iv—C6—H6A	109.0
N—C1—H1	118.0	C6^iv—C6—H6B	109.0
C7—C8—C9—C10	67.6 (3)

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

(II) poly[di-µ₄-succinato-µ₂-1,3-di-4-pyridylpropane-dicopper(II)]

Crystal data

[Cu2(C4H4O4)2(C13H14N2)]	F(000) = 1136
Mr = 557.5	Dx = 1.717 (1) Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2ybc	Cell parameters from 532 reflections
a = 15.563 (1) Å	θ = 3.1–22.5°
b = 6.4472 (7) Å	µ = 2.03 mm^−1
c = 24.100 (2) Å	T = 295 K
β = 116.913 (9)°	Prismatic, green
V = 2156.2 (4) Å^3	0.29 × 0.08 × 0.02 mm
Z = 4

Data collection

Stoe IPDS image-plate diffractometer	5101 independent reflections
Radiation source: fine focus sealed tube	1931 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.110
ω scans	θmax = 28.0°, θmin = 2.7°
Absorption correction: gaussian (JANA2006; Petříček et al., 2006)	h = −20→20
Tmin = 0.789, Tmax = 0.960	k = −8→8
25854 measured reflections	l = −31→31

Refinement

Refinement on F	0 constraints
R[F^2 > 2σ(F^2)] = 0.056	H-atom parameters constrained
wR(F^2) = 0.054	Weighting scheme based on measured s.u.'s w = 1/(σ^2(F) + 0.0001F^2)
S = 1.30	(Δ/σ)max = 0.039
5101 reflections	Δρmax = 0.54 e Å^−3
248 parameters	Δρmin = −0.85 e Å^−3
0 restraints

Special details

Refinement. Refinement of F against ALL reflections. The conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of I > σ(I) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement.

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

	x	y	z	Uiso*/Ueq
Cu1	0.17678 (9)	0.20595 (16)	0.19667 (6)	0.0246 (6)
Cu2	0.32283 (9)	0.27343 (17)	0.30679 (6)	0.0231 (5)
O1	0.1087 (5)	0.4238 (10)	0.2184 (3)	0.030 (4)
O2	0.2302 (6)	0.4674 (10)	0.3137 (4)	0.036 (4)
O3	0.1449 (6)	1.0085 (10)	0.2468 (4)	0.034 (4)
O4	0.2722 (6)	1.0525 (11)	0.3417 (3)	0.031 (3)
O5	0.2278 (6)	0.4183 (10)	0.1618 (4)	0.035 (4)
O6	0.3488 (5)	0.4771 (11)	0.2551 (3)	0.037 (3)
O7	0.2671 (6)	1.0048 (11)	0.1916 (4)	0.037 (4)
O8	0.3919 (6)	1.0638 (10)	0.2833 (3)	0.035 (4)
N1	1.0553 (5)	0.4178 (12)	0.6148 (3)	0.026 (4)
N2	0.4451 (5)	0.3947 (12)	0.3883 (3)	0.028 (4)
C1	0.1457 (5)	0.5050 (10)	0.27044 (11)	0.024 (5)
C2	0.0857 (5)	0.6562 (9)	0.2864 (2)	0.038 (4)
C3	0.1493 (5)	0.8239 (10)	0.33420 (12)	0.029 (6)
C4	0.1902 (5)	0.9729 (10)	0.30296 (16)	0.020 (5)
C5	0.35289 (6)	0.97821 (6)	0.23136 (2)	0.029 (5)
C6	0.41242 (6)	0.82608 (6)	0.21495 (4)	0.032 (4)
C7	0.35388 (6)	0.65488 (5)	0.17277 (4)	0.031 (4)
C8	0.30150 (6)	0.50731 (5)	0.19612 (2)	0.029 (5)
C9	0.99225 (4)	0.30834 (3)	0.57125 (3)	0.052 (5)
C10	0.906190 (19)	0.39072 (5)	0.522389 (17)	0.049 (3)
C11	0.88685 (5)	0.59386 (6)	0.51985 (3)	0.040 (4)
C12	0.9586 (5)	0.7155 (8)	0.5693 (3)	0.055 (6)
C13	1.0379 (5)	0.6173 (7)	0.6133 (4)	0.052 (5)
C14	0.8014 (3)	0.7055 (5)	0.4687 (2)	0.034 (5)
C15	0.7450 (4)	0.8301 (8)	0.4960 (3)	0.044 (6)
C16	0.6955 (5)	0.6951 (7)	0.5232 (4)	0.049 (5)
C17	0.6075 (4)	0.5938 (8)	0.4796 (3)	0.028 (4)
C18	0.6097 (4)	0.3878 (6)	0.4663 (3)	0.037 (4)
C19	0.52906 (7)	0.29295 (7)	0.42123 (5)	0.033 (5)
C20	0.4420 (4)	0.5969 (8)	0.4009 (3)	0.038 (4)
C21	0.5215 (5)	0.6972 (7)	0.4459 (3)	0.038 (4)
H2A	0.038887	0.724419	0.248349	0.0461*
H2B	0.048574	0.580051	0.30354	0.0461*
H3A	0.109952	0.901427	0.349367	0.035*
H3B	0.202335	0.755957	0.369449	0.035*
H6A	0.463076	0.766618	0.253198	0.0385*
H6B	0.44658	0.900914	0.195509	0.0385*
H7A	0.394043	0.575244	0.158728	0.037*
H7B	0.308042	0.713348	0.132683	0.037*
H9	1.003661	0.158814	0.57139	0.0619*
H10	0.860787	0.297759	0.490369	0.0583*
H12	0.950666	0.865683	0.571343	0.0655*
H13	1.085826	0.702886	0.646552	0.0625*
H14A	0.824469	0.799544	0.446426	0.0409*
H14B	0.758513	0.60379	0.438801	0.0409*
H15A	0.788812	0.925286	0.527984	0.0532*
H15B	0.697261	0.918154	0.463531	0.0532*
H16A	0.682812	0.775293	0.553289	0.0586*
H16B	0.740854	0.590835	0.550358	0.0586*
H18	0.668929	0.307646	0.488934	0.0449*
H19	0.532666	0.145476	0.412647	0.0391*
H20	0.38213	0.674753	0.377827	0.0457*
H21	0.516872	0.844721	0.453981	0.0458*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0210 (8)	0.0213 (6)	0.0303 (7)	−0.0041 (6)	0.0107 (6)	−0.0056 (5)
Cu2	0.0191 (8)	0.0227 (6)	0.0269 (6)	−0.0034 (6)	0.0100 (6)	−0.0047 (5)
O1	0.025 (5)	0.028 (4)	0.034 (4)	0.003 (3)	0.010 (4)	−0.007 (3)
O2	0.037 (6)	0.032 (4)	0.043 (5)	0.005 (3)	0.022 (4)	−0.006 (3)
O3	0.035 (6)	0.026 (4)	0.039 (4)	−0.006 (3)	0.016 (4)	0.003 (3)
O4	0.025 (5)	0.032 (4)	0.031 (4)	−0.009 (3)	0.010 (4)	−0.004 (3)
O5	0.039 (5)	0.035 (4)	0.031 (4)	−0.014 (3)	0.018 (4)	−0.003 (3)
O6	0.028 (5)	0.035 (4)	0.036 (4)	−0.019 (3)	0.006 (4)	−0.006 (3)
O7	0.019 (6)	0.039 (4)	0.047 (5)	0.003 (4)	0.008 (4)	−0.012 (3)
O8	0.028 (6)	0.035 (4)	0.038 (4)	0.003 (3)	0.010 (4)	−0.013 (3)
N1	0.022 (6)	0.025 (5)	0.023 (4)	−0.005 (4)	0.003 (4)	0.005 (3)
N2	0.033 (6)	0.025 (5)	0.030 (5)	−0.003 (4)	0.018 (5)	−0.001 (3)
C1	0.024 (7)	0.025 (6)	0.032 (6)	−0.006 (4)	0.021 (6)	0.000 (4)
C2	0.035 (6)	0.025 (5)	0.071 (5)	−0.008 (4)	0.038 (5)	−0.019 (4)
C3	0.044 (8)	0.016 (5)	0.046 (8)	0.001 (4)	0.037 (7)	0.000 (4)
C4	0.016 (7)	0.017 (5)	0.028 (6)	−0.008 (4)	0.009 (6)	−0.015 (4)
C5	0.027 (7)	0.014 (5)	0.055 (8)	−0.006 (5)	0.027 (7)	−0.005 (5)
C6	0.033 (6)	0.018 (5)	0.057 (5)	−0.008 (4)	0.031 (5)	−0.012 (4)
C7	0.043 (7)	0.017 (5)	0.039 (5)	−0.005 (4)	0.024 (5)	−0.003 (4)
C8	0.045 (7)	0.020 (5)	0.036 (7)	0.013 (5)	0.031 (6)	0.001 (5)
C9	0.035 (7)	0.021 (9)	0.088 (4)	0.000 (6)	0.018 (4)	0.004 (5)
C10	0.040 (5)	0.030 (4)	0.068 (4)	−0.008 (7)	0.017 (4)	−0.017 (6)
C11	0.040 (6)	0.056 (6)	0.028 (4)	0.000 (5)	0.018 (4)	0.007 (4)
C12	0.042 (8)	0.030 (5)	0.080 (7)	0.009 (5)	0.018 (7)	0.007 (5)
C13	0.036 (8)	0.036 (6)	0.047 (6)	−0.006 (5)	−0.014 (6)	0.005 (5)
C14	0.027 (7)	0.043 (8)	0.028 (6)	0.008 (5)	0.008 (6)	0.014 (5)
C15	0.027 (11)	0.036 (5)	0.050 (7)	−0.012 (6)	0.000 (7)	0.013 (5)
C16	0.042 (9)	0.077 (6)	0.013 (5)	−0.018 (5)	−0.001 (6)	−0.007 (4)
C17	0.013 (5)	0.042 (5)	0.025 (5)	−0.003 (4)	0.004 (4)	−0.014 (4)
C18	0.018 (6)	0.045 (6)	0.039 (5)	−0.007 (4)	0.003 (5)	0.001 (4)
C19	0.015 (7)	0.030 (7)	0.048 (6)	0.005 (5)	0.010 (5)	0.001 (5)
C20	0.025 (6)	0.028 (5)	0.044 (5)	0.003 (4)	0.001 (5)	−0.005 (4)
C21	0.036 (7)	0.019 (5)	0.048 (5)	−0.003 (4)	0.009 (5)	−0.005 (4)

Geometric parameters (Å, º)

Cu1—Cu2	2.6336 (17)	C12—C13	1.365 (8)
Cu1—O1	1.968 (9)	C14—C15	1.540 (9)
Cu1—O3^i	1.967 (9)	C15—C16	1.495 (11)
Cu1—O5	1.953 (9)	C16—C17	1.451 (8)
Cu1—O7^i	1.957 (9)	C17—C18	1.370 (7)
Cu2—O2	1.971 (9)	C17—C21	1.382 (8)
Cu2—O4^i	1.989 (9)	C18—C19	1.376 (5)
Cu2—O6	1.974 (9)	C20—C21	1.382 (7)
Cu2—O8^i	1.963 (9)	C2—H2A	0.980
O1—C1	1.234 (8)	C2—H2B	0.980
O2—C1	1.279 (9)	C3—H3A	0.980
O3—C4	1.232 (8)	C3—H3B	0.980
O4—C4	1.299 (9)	C6—H6A	0.9800
O5—C8	1.212 (7)	C6—H6B	0.9800
O6—C8	1.285 (7)	C7—H7A	0.9800
O7—C5	1.254 (7)	C7—H7B	0.9800
O8—C5	1.246 (7)	C9—H9	0.9800
N1—C9	1.277 (6)	C10—H10	0.9800
N1—C13	1.312 (9)	C12—H12	0.980
N2—C19	1.352 (7)	C13—H13	0.980
N2—C20	1.345 (9)	C14—H14A	0.980
C1—C2	1.515 (10)	C14—H14B	0.980
C2—C3	1.563 (7)	C15—H15A	0.980
C3—C4	1.526 (10)	C15—H15B	0.980
C5—C6	1.5194 (12)	C16—H16A	0.980
C6—C7	1.4977 (8)	C16—H16B	0.980
C7—C8	1.5171 (12)	C19—H19	0.9800
C9—C10	1.4265 (6)	C20—H20	0.980
C10—C11	1.3390 (6)	C18—H18	0.980
C11—C12	1.442 (6)	C21—H21	0.980
C11—C14	1.524 (4)
O1—Cu1—O3^i	89.0 (4)	C10—C11—C12	114.9 (2)
O1—Cu1—O5	89.3 (4)	C10—C11—C14	126.51 (14)
O1—Cu1—O7^i	168.1 (3)	C12—C11—C14	118.5 (3)
O3^i—Cu1—O5	169.3 (3)	C11—C12—C13	118.7 (4)
O3^i—Cu1—O7^i	89.9 (4)	N1—C13—C12	125.4 (5)
O5—Cu1—O7^i	89.6 (4)	C11—C14—C15	111.0 (4)
O2—Cu2—O4^i	88.5 (4)	C14—C15—C16	113.0 (4)
O2—Cu2—O6	89.9 (4)	C15—C16—C17	116.7 (6)
O2—Cu2—O8^i	167.9 (3)	C16—C17—C18	119.4 (5)
O4^i—Cu2—O6	167.6 (3)	C16—C17—C21	123.6 (5)
O4^i—Cu2—O8^i	90.1 (4)	C18—C17—C21	116.7 (5)
O6—Cu2—O8^i	88.9 (4)	C17—C18—C19	120.4 (4)
Cu1—O1—C1	120.9 (6)	N2—C19—C18	122.8 (4)
Cu2—O2—C1	125.0 (6)	N2—C20—C21	121.4 (5)
Cu1^ii—O3—C4	128.1 (6)	C17—C21—C20	121.3 (5)
Cu2^ii—O4—C4	115.3 (5)	C1—C2—H2A	109.0
Cu1—O5—C8	118.8 (5)	C1—C2—H2B	109.0
Cu2—O6—C8	128.3 (5)	C2—C3—H3A	109.0
Cu1^ii—O7—C5	126.1 (5)	C2—C3—H3B	109.0
Cu2^ii—O8—C5	120.9 (5)	C4—C3—H3A	109.0
C9—N1—C13	116.6 (5)	C4—C3—H3B	109.0
C19—N2—C20	117.5 (5)	C6—C7—H7A	109.0
O1—C1—O2	125.6 (8)	C6—C7—H7B	109.0
O1—C1—C2	118.2 (6)	C8—C7—H7A	109.0
O2—C1—C2	116.2 (5)	C8—C7—H7B	109.0
C1—C2—C3	112.0 (6)	C10—C9—H9	118.0
C2—C3—C4	109.8 (4)	C11—C10—H10	119.0
O3—C4—O4	127.2 (8)	C11—C12—H12	120.0
O3—C4—C3	120.0 (7)	C12—C13—H13	117.0
O4—C4—C3	112.8 (5)	C11—C14—H14A	109.0
O7—C5—O8	125.0 (6)	C11—C14—H14B	109.0
O7—C5—C6	116.9 (4)	C14—C15—H15A	109.0
O8—C5—C6	118.1 (4)	C14—C15—H15B	109.0
C5—C6—C7	113.40 (7)	C15—C16—H16A	109.0
C6—C7—C8	118.31 (8)	C15—C16—H16B	109.0
O5—C8—O6	125.0 (5)	C17—C18—H18	119.0
O5—C8—C7	123.0 (4)	C18—C19—H19	119.0
O6—C8—C7	111.7 (4)	C21—C20—H20	119.0
N1—C9—C10	123.9 (3)	C20—C21—H21	119.0
C9—C10—C11	120.63 (3)
C1—C2—C3—C4	70.6 (6)	C5—C6—C7—C8	−62.47 (4)

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