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Tetra­kis(μ2-2,2-di­methyl­propanoato-κ2O,O′)bis­­[(pyridine-κN)copper(II)]: a monoclinic polymorph

aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: edward.tiekink@gmail.com

(Received 23 April 2010; accepted 24 April 2010; online 30 April 2010)

The structure of the dinuclear title complex, [Cu2(C5H9O2)4(C5H5N)2], represents a monoclinic polymorph of the previously reported triclinic form [Blewett et al. (2006[Blewett, G., Esterhuysen, C., Bredenkamp, M. W. & Koch, K. R. (2006). Acta Cryst. E62, m420-m422.]). Acta Cryst. E62, m420–m422]. Each carboxyl­ate group is bidentate bridging and the distorted octa­hedral geometry about each CuII atom is completed by a pyridine N atom and the other Cu atom [Cu⋯Cu = 2.6139 (7) Å]. In the crystal, mol­ecules are connected into supra­molecular chains via ππ inter­actions formed by the pyridine rings [centroid–centroid distance = 3.552 (3) Å] and these are connected into a two-dimensional array in the ac plane by C—H⋯π contacts. One of the tert-butyl groups is disordered over two orientations in a 0.734 (6):0.266 (6) ratio.

Related literature

For the structure of the triclinic polymorph of the title compound, see: Blewett et al. (2006[Blewett, G., Esterhuysen, C., Bredenkamp, M. W. & Koch, K. R. (2006). Acta Cryst. E62, m420-m422.]). For background to copper(II) carboxyl­ates, see: Attard & Cullum (1990[Attard, G. S. & Cullum, P. R. (1990). Liq. Cryst. 8, 299-309.]); Kato et al. (1964[Kato, M., Jonassen, H. B., Fanning, J. C. & Cusachs, L. C. (1964). Chem. Rev. 64, 99-128.]); Melnik et al. (1984[Melnik, M., Dunaj-Jurco, M. & Handlovic, M. (1984). Inorg. Chim. Acta, 86, 185-190.]); Kawata et al. (1992[Kawata, T., Uekusa, H., Ohba, S., Furukawa, T., Tokii, T., Muto, Y. & Kato, M. (1992). Acta Cryst. B48, 253-261.]).

[Scheme 1]

Experimental

Crystal data
  • [Cu2(C5H9O2)4(C5H5N)2]

  • Mr = 689.80

  • Monoclinic, P 21 /n

  • a = 9.4758 (6) Å

  • b = 20.0192 (12) Å

  • c = 18.6136 (10) Å

  • β = 104.515 (3)°

  • V = 3418.3 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 1.29 mm−1

  • T = 100 K

  • 0.32 × 0.26 × 0.16 mm

Data collection
  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.682, Tmax = 0.820

  • 28775 measured reflections

  • 7077 independent reflections

  • 5583 reflections with I > 2σ(I)

  • Rint = 0.060

Refinement
  • R[F2 > 2σ(F2)] = 0.058

  • wR(F2) = 0.156

  • S = 1.13

  • 7077 reflections

  • 404 parameters

  • 12 restraints

  • H-atom parameters constrained

  • Δρmax = 1.26 e Å−3

  • Δρmin = −0.75 e Å−3

Table 1
Selected bond lengths (Å)

Cu1—O7 1.950 (3)
Cu1—O1 1.956 (3)
Cu1—O3 1.976 (3)
Cu1—O5 1.987 (3)
Cu1—N1 2.157 (3)
Cu2—O6 1.962 (3)
Cu2—O4 1.968 (3)
Cu2—O8 1.976 (3)
Cu2—O2 1.978 (3)
Cu2—N2 2.157 (3)

Table 2
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the N1,C21–C25 and N2,C26–C30 rings, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3c⋯Cg1i 0.98 2.90 3.609 (7) 130
C19b—H19f⋯Cg2ii 0.98 2.64 3.554 (19) 154
Symmetry codes: (i) x-1, y, z; (ii) x+1, y, z.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43. Submitted.]).

Supporting information


Comment top

Research on copper(II) carboxylates focuses upon their metallomesogenic properties (Attard & Cullum, 1990) and interesting magneto-structural relationship (Kato et al., 1964; Melnik et al., 1984; Kawata et al., 1992). However, the practical use of these complexes is hindered by their high melting points (greater than 523 K) and which are accompanied by thermal decomposition. Our research interest is to develop low-temperature copper(II) carboxylates as functional materials for use in the fields of catalysis, photonics, spintronics, and electronics. To realise this, we adopted the concepts of symmetry reduction by mixed ligands and the use of highly-branched alkylcarboxylates. This contribution reports the crystal structure of one of the starting materials to be used in the synthesis of such complexes, i.e. the title compound, (I).

The dinuclear structure of (I), Fig. 1, features two Cu atoms, separated by 2.6139 (7) Å, connected by four bidentate bridging carboxylate ligands. The final position in the disordered octahedral trans-CuNO4 donor set is occupied by a pyridine-N atom in each case. The structure resembles closely that described for the triclinic polymorph but with the latter being disposed about a centre of inversion (Blewett et al., 2006). The primary differences between the molecules is found in the relative disposition of the pyridine groups. In (I), the dihedral angles formed between the least-squares planes through the four O atoms and pyridine ring = 81.5 (1) ° for Cu1 and 88.6 (1) ° for Cu2, which compares to 89.38 (8) ° found in the triclinic structure. These differences are reflected in the dihedral angle of 12.93 (15) ° formed between the pyridine rings in (I) compared to 0 ° (from symmetry) in the triclinic polymorph. These differences not withstanding, the Cu–O bond distances are experimentally equivalent in the two forms but it is noted these cover are broader range in (I), i.e. 1.950 (3) to 1.987 (3) Å, compared with 1.963 (2) to 1.977 (2) Å; the Cu–N distances are indistinguishable. The Cu···Cu distance in (I), 2.6139 (7) Å, is shorter than 2.6229 (9) Å in the triclinic form.

A common feature of the crystal packing of both forms is the presence of significant ππ interactions between the pyridine rings. In (I), these [ring centroid(N1,C21—C25)···ring centroid(N2,C26—C30)i = 3.552 (3) Å, angle between planes = 9.2 (2) °, for i: 1/2+x, 1/2-y, 1/2+z] lead to supramolecular chains which are connected into a 2-D array in the ac plane by C–H···π contacts involving methyl-H atoms (one being derived from a disordered tert-butyl residue), Fig. 2 & Table 1. The layers are stacked along the b direction as illustrated in Fig. 3.

Related literature top

For the structure of the triclinic polymorph of the title compound, see: Blewett et al. (2006). For background to copper(II) carboxylates, see: Attard & Cullum (1990); Kato et al. (1964); Melnik et al. (1984); Kawata et al. (1992).

Experimental top

An aqueous solution (50 ml) of sodium carbonate (5.2 g, 0.049 mol) was added to an aqueous solution (50 ml) of 2,2-dimethylpropionic acid (10 g, 0.098 mol) and the mixture was stirred at 323 K. After 30 min, a solution of CuCl2.2H2O (8.33 g, 0.049 mol) dissolved in a minimum amount of water was added followed by addition of several drops of pyridine. The mixture was stirred for another 30 min. and then set aside at room temperature for a week whereupon green blocks of (I) were obtained. Both DSC and TGA data indicate that the material did not melt, but decomposed at 408 K. CHN analyses (%), Found: C, 52.17; H, 6.75; N, 4.16. Calc'd: C, 52.23; H, 6.72; N, 4.05.

Refinement top

Carbon-bound H-atoms were placed in calculated positions (C—H 0.95 to 0.98 Å) and were included in the refinement in the riding model approximation, with Uiso(H) set to 1.2 to 1.5Uequiv(C). One of the tert-butyl groups was found to be disordered with two positions being resolved for each of the methyl groups. From anisotropic refinement, the major component of the disorder had a site occupancy factor = 0.734 (6). The C–C bond distances for the disordered group were refined with the distance restraint 1.52±0.01 Å, and the anisotropic displacement parameters for pairs of disordered atoms were constrained to be equivalent with the EADP command in SHELXL-97 (Sheldrick, 2008). The maximum and minimum residual electron density peaks of 1.26 and 0.75 e Å-3, respectively, were located 1.43 Å and 0.24 Å from the H29 and C19b atoms, respectively.

Structure description top

Research on copper(II) carboxylates focuses upon their metallomesogenic properties (Attard & Cullum, 1990) and interesting magneto-structural relationship (Kato et al., 1964; Melnik et al., 1984; Kawata et al., 1992). However, the practical use of these complexes is hindered by their high melting points (greater than 523 K) and which are accompanied by thermal decomposition. Our research interest is to develop low-temperature copper(II) carboxylates as functional materials for use in the fields of catalysis, photonics, spintronics, and electronics. To realise this, we adopted the concepts of symmetry reduction by mixed ligands and the use of highly-branched alkylcarboxylates. This contribution reports the crystal structure of one of the starting materials to be used in the synthesis of such complexes, i.e. the title compound, (I).

The dinuclear structure of (I), Fig. 1, features two Cu atoms, separated by 2.6139 (7) Å, connected by four bidentate bridging carboxylate ligands. The final position in the disordered octahedral trans-CuNO4 donor set is occupied by a pyridine-N atom in each case. The structure resembles closely that described for the triclinic polymorph but with the latter being disposed about a centre of inversion (Blewett et al., 2006). The primary differences between the molecules is found in the relative disposition of the pyridine groups. In (I), the dihedral angles formed between the least-squares planes through the four O atoms and pyridine ring = 81.5 (1) ° for Cu1 and 88.6 (1) ° for Cu2, which compares to 89.38 (8) ° found in the triclinic structure. These differences are reflected in the dihedral angle of 12.93 (15) ° formed between the pyridine rings in (I) compared to 0 ° (from symmetry) in the triclinic polymorph. These differences not withstanding, the Cu–O bond distances are experimentally equivalent in the two forms but it is noted these cover are broader range in (I), i.e. 1.950 (3) to 1.987 (3) Å, compared with 1.963 (2) to 1.977 (2) Å; the Cu–N distances are indistinguishable. The Cu···Cu distance in (I), 2.6139 (7) Å, is shorter than 2.6229 (9) Å in the triclinic form.

A common feature of the crystal packing of both forms is the presence of significant ππ interactions between the pyridine rings. In (I), these [ring centroid(N1,C21—C25)···ring centroid(N2,C26—C30)i = 3.552 (3) Å, angle between planes = 9.2 (2) °, for i: 1/2+x, 1/2-y, 1/2+z] lead to supramolecular chains which are connected into a 2-D array in the ac plane by C–H···π contacts involving methyl-H atoms (one being derived from a disordered tert-butyl residue), Fig. 2 & Table 1. The layers are stacked along the b direction as illustrated in Fig. 3.

For the structure of the triclinic polymorph of the title compound, see: Blewett et al. (2006). For background to copper(II) carboxylates, see: Attard & Cullum (1990); Kato et al. (1964); Melnik et al. (1984); Kawata et al. (1992).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing displacement ellipsoids at the 50% probability level. Only the major component of the disordered tert-butyl group is shown for reasons of clarity.
[Figure 2] Fig. 2. The 2-D array in the ac plane in (I) mediated by ππ and C–H···π interactions, shown as purple and orange dashed lines, respectively. Colour code: Cu, orange; O, red; N, blue; C, grey; and H, green.
[Figure 3] Fig. 3. Packing of layers in (I) along the b axis. Colour code: Cu, orange; O, red; N, blue; C, grey; and H, green.
Tetrakis(µ2-2,2-dimethylpropanoato-κ2O,O')bis[(pyridine- κN)copper(II)] top
Crystal data top
[Cu2(C5H9O2)4(C5H5N)2]F(000) = 1448
Mr = 689.80Dx = 1.340 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 6465 reflections
a = 9.4758 (6) Åθ = 2.2–28.4°
b = 20.0192 (12) ŵ = 1.29 mm1
c = 18.6136 (10) ÅT = 100 K
β = 104.515 (3)°Block, green
V = 3418.3 (4) Å30.32 × 0.26 × 0.16 mm
Z = 4
Data collection top
Bruker SMART APEX CCD
diffractometer
7077 independent reflections
Radiation source: fine-focus sealed tube5583 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.060
ω scansθmax = 26.5°, θmin = 1.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1111
Tmin = 0.682, Tmax = 0.820k = 2525
28775 measured reflectionsl = 2323
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.058Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.156H-atom parameters constrained
S = 1.13 w = 1/[σ2(Fo2) + (0.0532P)2 + 12.7516P]
where P = (Fo2 + 2Fc2)/3
7077 reflections(Δ/σ)max = 0.001
404 parametersΔρmax = 1.26 e Å3
12 restraintsΔρmin = 0.75 e Å3
Crystal data top
[Cu2(C5H9O2)4(C5H5N)2]V = 3418.3 (4) Å3
Mr = 689.80Z = 4
Monoclinic, P21/nMo Kα radiation
a = 9.4758 (6) ŵ = 1.29 mm1
b = 20.0192 (12) ÅT = 100 K
c = 18.6136 (10) Å0.32 × 0.26 × 0.16 mm
β = 104.515 (3)°
Data collection top
Bruker SMART APEX CCD
diffractometer
7077 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
5583 reflections with I > 2σ(I)
Tmin = 0.682, Tmax = 0.820Rint = 0.060
28775 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.05812 restraints
wR(F2) = 0.156H-atom parameters constrained
S = 1.13 w = 1/[σ2(Fo2) + (0.0532P)2 + 12.7516P]
where P = (Fo2 + 2Fc2)/3
7077 reflectionsΔρmax = 1.26 e Å3
404 parametersΔρmin = 0.75 e Å3
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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 (Å2) top
xyzUiso*/UeqOcc. (<1)
Cu10.45858 (5)0.21308 (2)0.12035 (3)0.01076 (14)
Cu20.26828 (5)0.28113 (2)0.02145 (3)0.01059 (14)
O10.2929 (3)0.15985 (17)0.13229 (18)0.0249 (8)
O20.1310 (3)0.21490 (17)0.04446 (18)0.0234 (7)
O30.4621 (4)0.15777 (16)0.03288 (17)0.0246 (8)
O40.3063 (4)0.21771 (15)0.05224 (16)0.0206 (7)
O50.4194 (4)0.27884 (16)0.19295 (16)0.0227 (7)
O60.2568 (3)0.33601 (16)0.10715 (16)0.0219 (7)
O70.5986 (3)0.27532 (16)0.09663 (18)0.0233 (7)
O80.4386 (3)0.33408 (16)0.01196 (18)0.0217 (7)
N10.6203 (4)0.15694 (17)0.19951 (18)0.0127 (7)
N20.1082 (4)0.34034 (17)0.05504 (18)0.0114 (7)
C10.1662 (5)0.1693 (2)0.0920 (2)0.0162 (9)
C20.0475 (5)0.1208 (2)0.1027 (3)0.0229 (10)
C30.0191 (7)0.1362 (4)0.1771 (3)0.0458 (16)
H3A0.02120.18130.17630.069*
H3B0.11060.13340.21570.069*
H3C0.05070.10380.18760.069*
C40.1053 (7)0.0488 (3)0.1029 (4)0.0405 (14)
H4A0.19480.04400.14260.061*
H4B0.12620.03930.05490.061*
H4C0.03170.01750.11120.061*
C50.0901 (6)0.1281 (4)0.0406 (4)0.0524 (19)
H5A0.15890.09250.04460.079*
H5B0.06560.12460.00740.079*
H5C0.13470.17160.04440.079*
C60.3892 (4)0.1687 (2)0.0318 (2)0.0134 (8)
C70.3937 (5)0.1150 (2)0.0905 (2)0.0151 (9)
C80.5456 (5)0.0838 (3)0.0754 (3)0.0260 (11)
H8A0.57100.06430.02550.039*
H8B0.61700.11830.07890.039*
H8C0.54620.04880.11210.039*
C90.2810 (5)0.0621 (2)0.0821 (3)0.0232 (10)
H9A0.31110.04190.03260.035*
H9B0.27490.02730.11990.035*
H9C0.18540.08320.08840.035*
C100.3515 (5)0.1443 (2)0.1687 (2)0.0230 (10)
H10A0.35510.10910.20490.035*
H10B0.41980.18000.17280.035*
H10C0.25250.16250.17870.035*
C110.3319 (5)0.3263 (2)0.1724 (2)0.0146 (8)
C120.3165 (5)0.3794 (2)0.2300 (2)0.0188 (9)
C130.1568 (6)0.3994 (3)0.2176 (3)0.0307 (12)
H13A0.14830.43480.25260.046*
H13B0.09970.36050.22560.046*
H13C0.12000.41560.16670.046*
C140.4075 (6)0.4394 (3)0.2171 (3)0.0332 (12)
H14A0.37250.45480.16570.050*
H14B0.51000.42620.22630.050*
H14C0.39800.47560.25100.050*
C150.3755 (5)0.3530 (3)0.3093 (2)0.0244 (10)
H15A0.37130.38860.34490.037*
H15B0.47670.33850.31600.037*
H15C0.31610.31510.31770.037*
C160.5650 (5)0.3216 (2)0.0502 (2)0.0140 (8)
C17A0.6897 (5)0.3671 (2)0.0410 (2)0.0239 (10)0.734 (6)
C18A0.8277 (7)0.3287 (4)0.0437 (5)0.0402 (19)0.734 (6)
H18A0.81520.30200.00160.060*0.734 (6)
H18B0.84890.29900.08700.060*0.734 (6)
H18C0.90870.36000.04750.060*0.734 (6)
C19A0.6466 (8)0.4147 (4)0.0237 (4)0.0373 (19)0.734 (6)
H19A0.72320.44830.02030.056*0.734 (6)
H19B0.55500.43690.02260.056*0.734 (6)
H19C0.63360.38980.07020.056*0.734 (6)
C20A0.7221 (9)0.4117 (4)0.1122 (4)0.0397 (19)0.734 (6)
H20A0.76200.38400.15590.060*0.734 (6)
H20B0.63170.43290.11690.060*0.734 (6)
H20C0.79300.44630.10820.060*0.734 (6)
C17B0.6897 (5)0.3671 (2)0.0410 (2)0.0239 (10)0.266 (6)
C18B0.8322 (14)0.3532 (12)0.0968 (11)0.0402 (19)0.266 (6)
H18D0.91040.37850.08350.060*0.266 (6)
H18E0.85400.30530.09690.060*0.266 (6)
H18F0.82470.36660.14640.060*0.266 (6)
C19B0.711 (2)0.3343 (10)0.0311 (8)0.0373 (19)0.266 (6)
H19D0.64140.35360.07410.056*0.266 (6)
H19E0.69430.28600.02950.056*0.266 (6)
H19F0.81060.34250.03530.056*0.266 (6)
C20B0.636 (2)0.4363 (6)0.0178 (13)0.0397 (19)0.266 (6)
H20D0.59690.45660.05680.060*0.266 (6)
H20E0.55820.43390.02830.060*0.266 (6)
H20F0.71620.46350.00970.060*0.266 (6)
C210.6186 (5)0.0903 (2)0.2011 (3)0.0212 (10)
H210.55430.06710.16150.025*
C220.7063 (6)0.0535 (2)0.2577 (3)0.0266 (11)
H220.70170.00610.25720.032*
C230.8012 (5)0.0870 (3)0.3153 (2)0.0247 (11)
H230.86280.06290.35490.030*
C240.8046 (5)0.1551 (3)0.3142 (2)0.0234 (10)
H240.86810.17930.35310.028*
C250.7131 (5)0.1884 (2)0.2548 (2)0.0215 (10)
H250.71700.23580.25360.026*
C260.0947 (5)0.4055 (2)0.0447 (2)0.0173 (9)
H260.15610.42560.00200.021*
C270.0046 (5)0.4454 (2)0.0933 (3)0.0246 (10)
H270.01340.49150.08330.030*
C280.0911 (5)0.4162 (3)0.1571 (3)0.0259 (11)
H280.15860.44250.19220.031*
C290.0778 (5)0.3487 (3)0.1689 (3)0.0242 (10)
H290.13610.32760.21190.029*
C300.0230 (5)0.3123 (2)0.1163 (2)0.0182 (9)
H300.03200.26570.12390.022*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.0098 (2)0.0124 (3)0.0083 (2)0.00001 (19)0.00105 (18)0.00013 (18)
Cu20.0095 (2)0.0119 (3)0.0086 (2)0.00012 (19)0.00098 (18)0.00001 (18)
O10.0145 (16)0.0320 (19)0.0222 (17)0.0075 (14)0.0069 (13)0.0127 (14)
O20.0133 (15)0.0284 (18)0.0257 (17)0.0046 (13)0.0005 (13)0.0113 (14)
O30.0311 (19)0.0243 (18)0.0120 (15)0.0147 (14)0.0063 (13)0.0042 (13)
O40.0292 (18)0.0195 (16)0.0103 (14)0.0108 (14)0.0002 (13)0.0005 (12)
O50.0270 (18)0.0248 (18)0.0126 (15)0.0133 (14)0.0021 (13)0.0028 (13)
O60.0237 (17)0.0254 (17)0.0123 (15)0.0105 (14)0.0032 (13)0.0040 (13)
O70.0134 (15)0.0272 (18)0.0266 (17)0.0039 (13)0.0001 (13)0.0112 (14)
O80.0130 (15)0.0225 (17)0.0266 (17)0.0031 (13)0.0010 (13)0.0084 (13)
N10.0112 (17)0.0171 (18)0.0079 (16)0.0042 (14)0.0012 (13)0.0012 (13)
N20.0096 (16)0.0158 (17)0.0089 (16)0.0004 (13)0.0022 (13)0.0010 (13)
C10.019 (2)0.019 (2)0.0090 (19)0.0055 (17)0.0001 (16)0.0002 (16)
C20.017 (2)0.029 (3)0.021 (2)0.0090 (19)0.0013 (18)0.0088 (19)
C30.036 (3)0.072 (5)0.037 (3)0.017 (3)0.023 (3)0.005 (3)
C40.046 (4)0.026 (3)0.052 (4)0.013 (3)0.017 (3)0.006 (3)
C50.027 (3)0.060 (4)0.055 (4)0.026 (3)0.018 (3)0.026 (3)
C60.013 (2)0.014 (2)0.0116 (19)0.0021 (16)0.0015 (16)0.0010 (16)
C70.014 (2)0.019 (2)0.0113 (19)0.0026 (17)0.0004 (16)0.0039 (16)
C80.025 (3)0.028 (3)0.024 (2)0.010 (2)0.003 (2)0.005 (2)
C90.031 (3)0.018 (2)0.020 (2)0.006 (2)0.006 (2)0.0052 (18)
C100.029 (3)0.026 (3)0.012 (2)0.008 (2)0.0003 (19)0.0005 (18)
C110.015 (2)0.016 (2)0.014 (2)0.0002 (17)0.0057 (17)0.0002 (16)
C120.026 (2)0.014 (2)0.015 (2)0.0071 (18)0.0036 (18)0.0018 (17)
C130.028 (3)0.044 (3)0.019 (2)0.020 (2)0.003 (2)0.000 (2)
C140.047 (3)0.022 (3)0.029 (3)0.008 (2)0.008 (2)0.007 (2)
C150.031 (3)0.030 (3)0.010 (2)0.012 (2)0.0025 (19)0.0015 (18)
C160.014 (2)0.020 (2)0.0075 (18)0.0022 (17)0.0009 (16)0.0057 (16)
C17A0.015 (2)0.035 (3)0.022 (2)0.002 (2)0.0027 (19)0.007 (2)
C18A0.021 (3)0.044 (5)0.062 (5)0.001 (3)0.022 (4)0.008 (4)
C19A0.019 (3)0.048 (4)0.041 (4)0.011 (3)0.001 (3)0.021 (4)
C20A0.039 (4)0.047 (5)0.035 (4)0.028 (4)0.012 (3)0.013 (3)
C17B0.015 (2)0.035 (3)0.022 (2)0.002 (2)0.0027 (19)0.007 (2)
C18B0.021 (3)0.044 (5)0.062 (5)0.001 (3)0.022 (4)0.008 (4)
C19B0.019 (3)0.048 (4)0.041 (4)0.011 (3)0.001 (3)0.021 (4)
C20B0.039 (4)0.047 (5)0.035 (4)0.028 (4)0.012 (3)0.013 (3)
C210.024 (2)0.017 (2)0.020 (2)0.0008 (19)0.0002 (18)0.0012 (18)
C220.033 (3)0.018 (2)0.027 (3)0.008 (2)0.003 (2)0.0081 (19)
C230.017 (2)0.039 (3)0.015 (2)0.012 (2)0.0027 (18)0.011 (2)
C240.017 (2)0.040 (3)0.010 (2)0.004 (2)0.0015 (17)0.0037 (19)
C250.019 (2)0.023 (2)0.018 (2)0.0034 (19)0.0050 (18)0.0082 (18)
C260.016 (2)0.017 (2)0.016 (2)0.0021 (17)0.0009 (17)0.0010 (17)
C270.023 (2)0.019 (2)0.030 (3)0.0036 (19)0.003 (2)0.004 (2)
C280.023 (2)0.036 (3)0.016 (2)0.008 (2)0.0007 (19)0.009 (2)
C290.016 (2)0.036 (3)0.017 (2)0.006 (2)0.0017 (18)0.004 (2)
C300.013 (2)0.024 (2)0.015 (2)0.0032 (18)0.0026 (17)0.0068 (17)
Geometric parameters (Å, º) top
Cu1—O71.950 (3)C13—H13A0.9800
Cu1—O11.956 (3)C13—H13B0.9800
Cu1—O31.976 (3)C13—H13C0.9800
Cu1—O51.987 (3)C14—H14A0.9800
Cu1—N12.157 (3)C14—H14B0.9800
Cu1—Cu22.6139 (7)C14—H14C0.9800
Cu2—O61.962 (3)C15—H15A0.9800
Cu2—O41.968 (3)C15—H15B0.9800
Cu2—O81.976 (3)C15—H15C0.9800
Cu2—O21.978 (3)C16—C17B1.535 (6)
Cu2—N22.157 (3)C16—C17A1.535 (6)
O1—C11.261 (5)C17A—C18A1.506 (7)
O2—C11.257 (5)C17A—C19A1.510 (6)
O3—C61.247 (5)C17A—C20A1.563 (7)
O4—C61.255 (5)C18A—H18A0.9800
O5—C111.256 (5)C18A—H18B0.9800
O6—C111.260 (5)C18A—H18C0.9800
O7—C161.253 (5)C19A—H19A0.9800
O8—C161.255 (5)C19A—H19B0.9800
N1—C251.332 (5)C19A—H19C0.9800
N1—C211.335 (6)C20A—H20A0.9800
N2—C261.329 (5)C20A—H20B0.9800
N2—C301.343 (5)C20A—H20C0.9800
C1—C21.535 (6)C17B—C20B1.503 (10)
C2—C31.506 (7)C17B—C18B1.508 (9)
C2—C51.518 (7)C17B—C19B1.553 (9)
C2—C41.541 (8)C18B—H18D0.9800
C3—H3A0.9800C18B—H18E0.9800
C3—H3B0.9800C18B—H18F0.9800
C3—H3C0.9800C19B—H19D0.9800
C4—H4A0.9800C19B—H19E0.9800
C4—H4B0.9800C19B—H19F0.9800
C4—H4C0.9800C20B—H20D0.9800
C5—H5A0.9800C20B—H20E0.9800
C5—H5B0.9800C20B—H20F0.9800
C5—H5C0.9800C21—C221.379 (6)
C6—C71.541 (6)C21—H210.9500
C7—C101.527 (6)C22—C231.388 (7)
C7—C81.530 (6)C22—H220.9500
C7—C91.540 (6)C23—C241.364 (7)
C8—H8A0.9800C23—H230.9500
C8—H8B0.9800C24—C251.392 (6)
C8—H8C0.9800C24—H240.9500
C9—H9A0.9800C25—H250.9500
C9—H9B0.9800C26—C271.383 (6)
C9—H9C0.9800C26—H260.9500
C10—H10A0.9800C27—C281.391 (7)
C10—H10B0.9800C27—H270.9500
C10—H10C0.9800C28—C291.380 (7)
C11—C121.542 (6)C28—H280.9500
C12—C131.526 (6)C29—C301.391 (6)
C12—C141.532 (7)C29—H290.9500
C12—C151.535 (6)C30—H300.9500
O7—Cu1—O1170.12 (13)C7—C10—H10C109.5
O7—Cu1—O391.07 (15)H10A—C10—H10C109.5
O1—Cu1—O388.17 (15)H10B—C10—H10C109.5
O7—Cu1—O589.11 (15)O5—C11—O6125.5 (4)
O1—Cu1—O589.51 (15)O5—C11—C12118.7 (4)
O3—Cu1—O5167.45 (12)O6—C11—C12115.8 (4)
O7—Cu1—N194.62 (13)C13—C12—C14110.2 (4)
O1—Cu1—N195.25 (13)C13—C12—C15110.1 (4)
O3—Cu1—N196.60 (13)C14—C12—C15109.7 (4)
O5—Cu1—N195.89 (12)C13—C12—C11109.8 (4)
O7—Cu1—Cu284.03 (9)C14—C12—C11106.1 (4)
O1—Cu1—Cu286.11 (9)C15—C12—C11110.9 (3)
O3—Cu1—Cu282.12 (9)C12—C13—H13A109.5
O5—Cu1—Cu285.42 (9)C12—C13—H13B109.5
N1—Cu1—Cu2178.11 (9)H13A—C13—H13B109.5
O6—Cu2—O4170.13 (12)C12—C13—H13C109.5
O6—Cu2—O889.16 (14)H13A—C13—H13C109.5
O4—Cu2—O889.27 (14)H13B—C13—H13C109.5
O6—Cu2—O291.47 (14)C12—C14—H14A109.5
O4—Cu2—O287.93 (14)C12—C14—H14B109.5
O8—Cu2—O2167.25 (13)H14A—C14—H14B109.5
O6—Cu2—N293.19 (13)C12—C14—H14C109.5
O4—Cu2—N296.66 (12)H14A—C14—H14C109.5
O8—Cu2—N295.82 (12)H14B—C14—H14C109.5
O2—Cu2—N296.86 (13)C12—C15—H15A109.5
O6—Cu2—Cu183.59 (9)C12—C15—H15B109.5
O4—Cu2—Cu186.57 (9)H15A—C15—H15B109.5
O8—Cu2—Cu184.71 (9)C12—C15—H15C109.5
O2—Cu2—Cu182.71 (9)H15A—C15—H15C109.5
N2—Cu2—Cu1176.73 (9)H15B—C15—H15C109.5
C1—O1—Cu1121.5 (3)O7—C16—O8125.4 (4)
C1—O2—Cu2124.5 (3)O7—C16—C17B116.5 (4)
C6—O3—Cu1125.2 (3)O8—C16—C17B118.1 (4)
C6—O4—Cu2120.2 (3)O7—C16—C17A116.5 (4)
C11—O5—Cu1121.1 (3)O8—C16—C17A118.1 (4)
C11—O6—Cu2124.4 (3)C18A—C17A—C19A114.0 (5)
C16—O7—Cu1124.0 (3)C18A—C17A—C16112.3 (4)
C16—O8—Cu2121.8 (3)C19A—C17A—C16113.6 (4)
C25—N1—C21117.7 (4)C18A—C17A—C20A106.2 (5)
C25—N1—Cu1120.0 (3)C19A—C17A—C20A105.8 (6)
C21—N1—Cu1121.7 (3)C16—C17A—C20A103.8 (4)
C26—N2—C30118.3 (4)C20B—C17B—C18B123.4 (12)
C26—N2—Cu2121.4 (3)C20B—C17B—C16111.2 (9)
C30—N2—Cu2120.3 (3)C18B—C17B—C16113.3 (9)
O2—C1—O1124.9 (4)C20B—C17B—C19B104.5 (12)
O2—C1—C2118.5 (4)C18B—C17B—C19B103.3 (12)
O1—C1—C2116.6 (4)C16—C17B—C19B96.6 (8)
C3—C2—C5111.3 (5)C17B—C18B—H18D109.5
C3—C2—C1107.2 (4)C17B—C18B—H18E109.5
C5—C2—C1111.0 (4)H18D—C18B—H18E109.5
C3—C2—C4109.5 (5)C17B—C18B—H18F109.5
C5—C2—C4109.1 (5)H18D—C18B—H18F109.5
C1—C2—C4108.7 (4)H18E—C18B—H18F109.5
C2—C3—H3A109.5C17B—C19B—H19D109.5
C2—C3—H3B109.5C17B—C19B—H19E109.5
H3A—C3—H3B109.5H19D—C19B—H19E109.5
C2—C3—H3C109.5C17B—C19B—H19F109.5
H3A—C3—H3C109.5H19D—C19B—H19F109.5
H3B—C3—H3C109.5H19E—C19B—H19F109.5
C2—C4—H4A109.5C17B—C20B—H20D109.5
C2—C4—H4B109.5C17B—C20B—H20E109.5
H4A—C4—H4B109.5H20D—C20B—H20E109.5
C2—C4—H4C109.5C17B—C20B—H20F109.5
H4A—C4—H4C109.5H20D—C20B—H20F109.5
H4B—C4—H4C109.5H20E—C20B—H20F109.5
C2—C5—H5A109.5N1—C21—C22122.8 (4)
C2—C5—H5B109.5N1—C21—H21118.6
H5A—C5—H5B109.5C22—C21—H21118.6
C2—C5—H5C109.5C21—C22—C23118.9 (4)
H5A—C5—H5C109.5C21—C22—H22120.6
H5B—C5—H5C109.5C23—C22—H22120.6
O3—C6—O4125.6 (4)C24—C23—C22118.9 (4)
O3—C6—C7117.1 (4)C24—C23—H23120.5
O4—C6—C7117.2 (3)C22—C23—H23120.5
C10—C7—C8110.0 (4)C23—C24—C25118.5 (4)
C10—C7—C9109.8 (4)C23—C24—H24120.7
C8—C7—C9110.2 (4)C25—C24—H24120.7
C10—C7—C6111.2 (4)N1—C25—C24123.1 (4)
C8—C7—C6110.3 (3)N1—C25—H25118.4
C9—C7—C6105.3 (3)C24—C25—H25118.4
C7—C8—H8A109.5N2—C26—C27123.2 (4)
C7—C8—H8B109.5N2—C26—H26118.4
H8A—C8—H8B109.5C27—C26—H26118.4
C7—C8—H8C109.5C26—C27—C28118.3 (4)
H8A—C8—H8C109.5C26—C27—H27120.9
H8B—C8—H8C109.5C28—C27—H27120.9
C7—C9—H9A109.5C29—C28—C27119.3 (4)
C7—C9—H9B109.5C29—C28—H28120.4
H9A—C9—H9B109.5C27—C28—H28120.4
C7—C9—H9C109.5C28—C29—C30118.4 (4)
H9A—C9—H9C109.5C28—C29—H29120.8
H9B—C9—H9C109.5C30—C29—H29120.8
C7—C10—H10A109.5N2—C30—C29122.6 (4)
C7—C10—H10B109.5N2—C30—H30118.7
H10A—C10—H10B109.5C29—C30—H30118.7
O7—Cu1—Cu2—O689.67 (15)Cu2—O2—C1—C2179.0 (3)
O1—Cu1—Cu2—O689.73 (15)Cu1—O1—C1—O24.5 (6)
O3—Cu1—Cu2—O6178.42 (15)Cu1—O1—C1—C2175.5 (3)
O5—Cu1—Cu2—O60.09 (15)O2—C1—C2—C3109.5 (5)
O7—Cu1—Cu2—O489.67 (15)O1—C1—C2—C370.5 (6)
O1—Cu1—Cu2—O490.93 (15)O2—C1—C2—C512.2 (7)
O3—Cu1—Cu2—O42.25 (15)O1—C1—C2—C5167.8 (5)
O5—Cu1—Cu2—O4179.25 (14)O2—C1—C2—C4132.2 (5)
O7—Cu1—Cu2—O80.08 (14)O1—C1—C2—C447.8 (6)
O1—Cu1—Cu2—O8179.48 (15)Cu1—O3—C6—O43.0 (7)
O3—Cu1—Cu2—O891.83 (15)Cu1—O3—C6—C7172.9 (3)
O5—Cu1—Cu2—O889.66 (15)Cu2—O4—C6—O35.9 (6)
O7—Cu1—Cu2—O2178.01 (15)Cu2—O4—C6—C7170.0 (3)
O1—Cu1—Cu2—O22.58 (15)O3—C6—C7—C10158.3 (4)
O3—Cu1—Cu2—O286.10 (15)O4—C6—C7—C1025.4 (5)
O5—Cu1—Cu2—O292.41 (15)O3—C6—C7—C836.1 (5)
O3—Cu1—O1—C177.8 (4)O4—C6—C7—C8147.7 (4)
O5—Cu1—O1—C189.8 (4)O3—C6—C7—C982.8 (5)
N1—Cu1—O1—C1174.3 (4)O4—C6—C7—C993.5 (4)
Cu2—Cu1—O1—C14.4 (3)Cu1—O5—C11—O63.2 (6)
O6—Cu2—O2—C181.5 (4)Cu1—O5—C11—C12174.4 (3)
O4—Cu2—O2—C188.6 (4)Cu2—O6—C11—O53.4 (7)
O8—Cu2—O2—C111.2 (9)Cu2—O6—C11—C12174.2 (3)
N2—Cu2—O2—C1174.9 (4)O5—C11—C12—C13140.4 (4)
Cu1—Cu2—O2—C11.8 (3)O6—C11—C12—C1341.7 (5)
O7—Cu1—O3—C683.2 (4)O5—C11—C12—C14100.5 (5)
O1—Cu1—O3—C687.0 (4)O6—C11—C12—C1477.4 (5)
O5—Cu1—O3—C67.5 (9)O5—C11—C12—C1518.6 (6)
N1—Cu1—O3—C6178.0 (4)O6—C11—C12—C15163.6 (4)
Cu2—Cu1—O3—C60.6 (4)Cu1—O7—C16—O80.9 (6)
O8—Cu2—O4—C689.4 (3)Cu1—O7—C16—C17B177.9 (3)
O2—Cu2—O4—C678.2 (3)Cu1—O7—C16—C17A177.9 (3)
N2—Cu2—O4—C6174.8 (3)Cu2—O8—C16—O71.0 (6)
Cu1—Cu2—O4—C64.7 (3)Cu2—O8—C16—C17B177.8 (3)
O7—Cu1—O5—C1182.7 (4)Cu2—O8—C16—C17A177.8 (3)
O1—Cu1—O5—C1187.5 (4)O7—C16—C17A—C18A39.7 (6)
O3—Cu1—O5—C118.2 (9)O8—C16—C17A—C18A141.4 (5)
N1—Cu1—O5—C11177.2 (4)C17B—C16—C17A—C18A0 (100)
Cu2—Cu1—O5—C111.4 (3)O7—C16—C17A—C19A171.0 (5)
O8—Cu2—O6—C1183.1 (4)O8—C16—C17A—C19A10.1 (7)
O2—Cu2—O6—C1184.2 (4)C17B—C16—C17A—C19A0 (82)
N2—Cu2—O6—C11178.9 (4)O7—C16—C17A—C20A74.6 (6)
Cu1—Cu2—O6—C111.7 (3)O8—C16—C17A—C20A104.2 (5)
O3—Cu1—O7—C1682.3 (4)C17B—C16—C17A—C20A0 (100)
O5—Cu1—O7—C1685.1 (4)O7—C16—C17B—C20B150.8 (10)
N1—Cu1—O7—C16179.0 (3)O8—C16—C17B—C20B28.1 (11)
Cu2—Cu1—O7—C160.3 (3)C17A—C16—C17B—C20B0 (4)
O6—Cu2—O8—C1683.1 (3)O7—C16—C17B—C18B6.7 (11)
O4—Cu2—O8—C1687.2 (3)O8—C16—C17B—C18B172.2 (11)
O2—Cu2—O8—C169.9 (9)C17A—C16—C17B—C18B0 (100)
N2—Cu2—O8—C16176.2 (3)O7—C16—C17B—C19B100.8 (8)
Cu1—Cu2—O8—C160.5 (3)O8—C16—C17B—C19B80.3 (9)
O7—Cu1—N1—C2552.8 (3)C17A—C16—C17B—C19B0 (100)
O1—Cu1—N1—C25126.9 (3)C25—N1—C21—C221.2 (7)
O3—Cu1—N1—C25144.4 (3)Cu1—N1—C21—C22169.9 (4)
O5—Cu1—N1—C2536.8 (4)N1—C21—C22—C230.5 (8)
O7—Cu1—N1—C21136.4 (4)C21—C22—C23—C240.1 (7)
O1—Cu1—N1—C2144.0 (4)C22—C23—C24—C250.4 (7)
O3—Cu1—N1—C2144.8 (4)C21—N1—C25—C241.6 (7)
O5—Cu1—N1—C21134.0 (3)Cu1—N1—C25—C24169.6 (4)
O6—Cu2—N2—C2632.0 (3)C23—C24—C25—N11.2 (7)
O4—Cu2—N2—C26147.4 (3)C30—N2—C26—C271.2 (6)
O8—Cu2—N2—C2657.5 (3)Cu2—N2—C26—C27178.6 (3)
O2—Cu2—N2—C26123.9 (3)N2—C26—C27—C282.1 (7)
O6—Cu2—N2—C30150.6 (3)C26—C27—C28—C291.6 (7)
O4—Cu2—N2—C3029.9 (3)C27—C28—C29—C300.4 (7)
O8—Cu2—N2—C30119.9 (3)C26—N2—C30—C290.1 (6)
O2—Cu2—N2—C3058.8 (3)Cu2—N2—C30—C29177.4 (3)
Cu2—O2—C1—O11.0 (7)C28—C29—C30—N20.5 (7)
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the N1,C21–C25 and N2,C26–C30 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C3—H3c···Cg1i0.982.903.609 (7)130
C19b—H19f···Cg2ii0.982.643.554 (19)154
Symmetry codes: (i) x1, y, z; (ii) x+1, y, z.

Experimental details

Crystal data
Chemical formula[Cu2(C5H9O2)4(C5H5N)2]
Mr689.80
Crystal system, space groupMonoclinic, P21/n
Temperature (K)100
a, b, c (Å)9.4758 (6), 20.0192 (12), 18.6136 (10)
β (°) 104.515 (3)
V3)3418.3 (4)
Z4
Radiation typeMo Kα
µ (mm1)1.29
Crystal size (mm)0.32 × 0.26 × 0.16
Data collection
DiffractometerBruker SMART APEX CCD
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.682, 0.820
No. of measured, independent and
observed [I > 2σ(I)] reflections
28775, 7077, 5583
Rint0.060
(sin θ/λ)max1)0.628
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.058, 0.156, 1.13
No. of reflections7077
No. of parameters404
No. of restraints12
H-atom treatmentH-atom parameters constrained
w = 1/[σ2(Fo2) + (0.0532P)2 + 12.7516P]
where P = (Fo2 + 2Fc2)/3
Δρmax, Δρmin (e Å3)1.26, 0.75

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006), publCIF (Westrip, 2010).

Selected bond lengths (Å) top
Cu1—O71.950 (3)Cu2—O61.962 (3)
Cu1—O11.956 (3)Cu2—O41.968 (3)
Cu1—O31.976 (3)Cu2—O81.976 (3)
Cu1—O51.987 (3)Cu2—O21.978 (3)
Cu1—N12.157 (3)Cu2—N22.157 (3)
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the N1,C21–C25 and N2,C26–C30 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C3—H3c···Cg1i0.982.903.609 (7)130
C19b—H19f···Cg2ii0.982.643.554 (19)154
Symmetry codes: (i) x1, y, z; (ii) x+1, y, z.
 

Footnotes

Additional correspondence author, e-mail: norbania@um.edu.my.

Acknowledgements

The authors thank the University of Malaya for funding this study through PPP (PS345/2010 A) and the Research University Fund (TA021/2009 A).

References

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