Tetra-μ-acetato-bis­[(pyridine N-oxide)copper(II)](Cu—Cu)

Cui, Y.; Gao, Q.; Zhang, C.-Y.; Xie, Y.-B.

doi:10.1107/S1600536809024222

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Page m850

doi:10.1107/S1600536809024222

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Tetra-μ-acetato-bis[(pyridine N-oxide)copper(II)](Cu—Cu)

Yue Cui,^a Qian Gao,^a Chao-Yan Zhang ^a and Ya-Bo Xie ^a ^*

^aCollege of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, People's Republic of China
^*Correspondence e-mail: xieyabo@bjut.edu.cn

(Received 26 May 2009; accepted 24 June 2009; online 1 July 2009)

The molecule of the title binuclear copper(II) complex, [Cu₂(CH₃COO)₄(C₅H₅NO)₂], occupies a special position on a crystallographic inversion centre; the coordination environment of the Cu^II atom is slightly distorted square-pyramidal and is made up of four O atoms belonging to four acetate groups in the basal plane with the O atom of pyridine N-oxide ligand in the apical position. The Cu—Cu distance is 2.6376 (6) Å.

Related literature

For the biological activity of binuclear copper(II) compounds, see: Li et al. (2007 ). For a related structure, see: Zhang (2009 ).

Experimental

Crystal data

[Cu₂(C₂H₃O₂)₄(C₅H₅NO)₂]
M_r = 553.46
Monoclinic, P 2₁ /c
a = 9.6737 (11) Å
b = 13.5886 (16) Å
c = 8.5236 (10) Å
β = 99.970 (2)°
V = 1103.5 (2) Å³
Z = 2
Mo Kα radiation
μ = 1.98 mm⁻¹
T = 296 K
0.2 × 0.2 × 0.2 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1998 ) T_min = 0.673, T_max = 0.680
5445 measured reflections
1936 independent reflections
1713 reflections with I > 2σ(I)
R_int = 0.015

Refinement

R[F² > 2σ(F²)] = 0.025
wR(F²) = 0.070
S = 1.07
1936 reflections
145 parameters
H-atom parameters constrained
Δρ_max = 0.43 e Å⁻³
Δρ_min = −0.33 e Å⁻³

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809024222/ya2100sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809024222/ya2100Isup2.hkl

checkCIF report

Comment top

The crystal structures of binuclear copper(II) complexes have been extensively studied because of their possible anticarcinogen properties (Li et al., 2007), and numerous papers dealing with binuclear copper complexes have been published (Zhang, 2009). Herein, we report the synthesis and crystal structure of a new binuclear copper complex.

The molecule of the title binuclear copper(II) complex, [Cu₂(C₂H₃O₂)₄(C₅H₅ON)₂], occupies a special position in the crystallographic inversion centre; coordination environment of the Cu^II atom represents a slightly distorted tetragonal pyramid and is made up of four oxygen atoms belonging to four acetato-group in the basal plane as well as the oxygen atom of pyridine N-oxide ligand in the apical position. The Cu—O bond distance between Cu^II atom and acetato O atoms vary from 1.9605 (18) Å to 1.9710 (18) Å, while the Cu—O bond distance involving Cu^II atom and the O atom of the pyridine N-oxide ligand is 2.1507 (18) Å. The Cu1—Cu1ⁱ distance is 2.6376 (6) Å [symmetry code (i): 1 - x, -y, -z].

Related literature top

For the biological activity of binuclear copper(II) compounds, see: Li et al. (2007). For a related structure, see: Zhang (2009).

Experimental top

A solution containing a 1:2:5 molar ratio of picolinic acid N-oxide (0.0139 g, 0.1 mmol), CuCO₃ (0.0247 g, 0.2 mmol) and acetic acid (1 ml, 0.5 mmol/ml) in a mixture of ethanol(5 ml) and water (10 ml) was sealed in a 25 ml teflon reactor and kept at 453 K for 3 days, then slowly cooled to 373 k and kept at this temperature for 24 h more. After cooling to room temperature, the mixture was filtered and the filtrate was allowed to stand at room temperature. Block crystals suitable for the X-ray investigation were collected.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. Molecular structure of the title compound with displacement ellipsoids drawn at the 30% probability level; hydrogen atoms are shown as small circles of arbitrary radius. The unlabelled atoms are derived by the symmetry transformation -x + 1, -y, -z.

Tetra-µ-acetato-bis[(pyridine N-oxide)copper(II)](Cu—Cu) top

Crystal data top

[Cu₂(C₂H₃O₂)₄(C₅H₅NO)₂]	F(000) = 564
M_r = 553.46	D_x = 1.666 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3911 reflections
a = 9.6737 (11) Å	θ = 2.6–27.9°
b = 13.5886 (16) Å	µ = 1.98 mm⁻¹
c = 8.5236 (10) Å	T = 296 K
β = 99.970 (2)°	Block, blue
V = 1103.5 (2) Å³	0.2 × 0.2 × 0.2 mm
Z = 2

Data collection top

Bruker SMART CCD area-detector diffractometer	1936 independent reflections
Radiation source: fine-focus sealed tube	1713 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.015
ϕ and ω scans	θ_max = 25.0°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 1998)	h = −10→11
T_min = 0.673, T_max = 0.680	k = −16→9
5445 measured reflections	l = −10→9

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.025	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.070	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0352P)² + 0.7718P] where P = (F_o² + 2F_c²)/3
1936 reflections	(Δ/σ)_max = 0.001
145 parameters	Δρ_max = 0.43 e Å⁻³
0 restraints	Δρ_min = −0.33 e Å⁻³

Crystal data top

[Cu₂(C₂H₃O₂)₄(C₅H₅NO)₂]	V = 1103.5 (2) Å³
M_r = 553.46	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 9.6737 (11) Å	µ = 1.98 mm⁻¹
b = 13.5886 (16) Å	T = 296 K
c = 8.5236 (10) Å	0.2 × 0.2 × 0.2 mm
β = 99.970 (2)°

Data collection top

Bruker SMART CCD area-detector diffractometer	1936 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1998)	1713 reflections with I > 2σ(I)
T_min = 0.673, T_max = 0.680	R_int = 0.015
5445 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.025	0 restraints
wR(F²) = 0.070	H-atom parameters constrained
S = 1.07	Δρ_max = 0.43 e Å⁻³
1936 reflections	Δρ_min = −0.33 e Å⁻³
145 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
O3	0.55087 (19)	−0.15687 (13)	−0.0542 (2)	0.0457 (5)
O4	0.69513 (18)	−0.02840 (14)	0.1692 (2)	0.0411 (4)
Cu1	0.38549 (3)	0.01927 (2)	0.05882 (3)	0.02846 (12)
O5	0.50246 (19)	0.00354 (14)	0.2694 (2)	0.0424 (4)
O2	0.35940 (18)	−0.12383 (13)	0.0480 (2)	0.0408 (4)
N1	0.11758 (19)	0.11134 (15)	0.1808 (2)	0.0330 (4)
C8	0.6302 (3)	−0.01859 (17)	0.2828 (3)	0.0335 (5)
O1	0.18110 (19)	0.03795 (15)	0.1215 (3)	0.0520 (5)
C6	0.4409 (3)	−0.18155 (18)	−0.0051 (3)	0.0349 (5)
C1	0.1856 (3)	0.1945 (2)	0.2326 (3)	0.0409 (6)
H1A	0.2801	0.2014	0.2261	0.049*
C5	−0.0186 (2)	0.1004 (2)	0.1894 (3)	0.0406 (6)
H5A	−0.0653	0.0428	0.1529	0.049*
C9	0.7115 (3)	−0.0358 (2)	0.4475 (3)	0.0506 (7)
H9A	0.8070	−0.0518	0.4408	0.076*
H9B	0.6700	−0.0892	0.4966	0.076*
H9C	0.7096	0.0228	0.5102	0.076*
C2	0.1170 (3)	0.2692 (2)	0.2948 (3)	0.0499 (7)
H2A	0.1650	0.3265	0.3302	0.060*
C4	−0.0892 (3)	0.1741 (2)	0.2519 (4)	0.0509 (7)
H4A	−0.1835	0.1658	0.2581	0.061*
C3	−0.0225 (3)	0.2599 (2)	0.3054 (4)	0.0545 (8)
H3A	−0.0702	0.3102	0.3474	0.065*
C7	0.4047 (3)	−0.2887 (2)	−0.0104 (4)	0.0530 (7)
H7A	0.3190	−0.2983	0.0300	0.080*
H7B	0.4789	−0.3249	0.0539	0.080*
H7C	0.3930	−0.3117	−0.1184	0.080*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O3	0.0419 (10)	0.0288 (9)	0.0715 (13)	−0.0013 (8)	0.0238 (9)	−0.0027 (9)
O4	0.0337 (9)	0.0532 (12)	0.0363 (9)	0.0075 (8)	0.0062 (7)	0.0057 (8)
Cu1	0.02487 (17)	0.02651 (18)	0.03512 (19)	0.00156 (11)	0.00833 (12)	0.00071 (11)
O5	0.0362 (10)	0.0558 (12)	0.0356 (9)	0.0061 (8)	0.0071 (7)	−0.0015 (8)
O2	0.0409 (10)	0.0286 (9)	0.0557 (11)	−0.0019 (7)	0.0158 (8)	0.0008 (8)
N1	0.0279 (10)	0.0374 (11)	0.0350 (10)	−0.0006 (9)	0.0088 (8)	−0.0034 (9)
C8	0.0374 (13)	0.0264 (12)	0.0364 (13)	−0.0007 (10)	0.0055 (10)	0.0015 (10)
O1	0.0339 (10)	0.0484 (12)	0.0788 (14)	−0.0019 (8)	0.0237 (9)	−0.0203 (10)
C6	0.0356 (13)	0.0277 (12)	0.0402 (13)	−0.0017 (10)	0.0034 (10)	0.0044 (10)
C1	0.0319 (13)	0.0444 (15)	0.0470 (15)	−0.0119 (11)	0.0089 (11)	−0.0035 (12)
C5	0.0275 (12)	0.0444 (15)	0.0512 (15)	−0.0077 (11)	0.0106 (11)	−0.0127 (12)
C9	0.0508 (16)	0.0627 (19)	0.0368 (15)	0.0086 (14)	0.0031 (12)	0.0055 (13)
C2	0.0540 (17)	0.0408 (15)	0.0554 (18)	−0.0122 (13)	0.0108 (13)	−0.0108 (13)
C4	0.0308 (14)	0.0589 (18)	0.0654 (18)	−0.0008 (12)	0.0146 (12)	−0.0178 (15)
C3	0.0526 (17)	0.0506 (18)	0.0626 (19)	0.0068 (14)	0.0162 (14)	−0.0180 (15)
C7	0.0568 (18)	0.0282 (14)	0.077 (2)	−0.0029 (12)	0.0187 (15)	0.0036 (14)

Geometric parameters (Å, º) top

O3—C6	1.254 (3)	C1—C2	1.369 (4)
O4—C8	1.250 (3)	C1—H1A	0.9300
Cu1—O5	1.9605 (18)	C5—C4	1.370 (4)
Cu1—O2	1.9610 (18)	C5—H5A	0.9300
Cu1—O4ⁱ	1.9685 (17)	C9—H9A	0.9600
Cu1—O3ⁱ	1.9710 (18)	C9—H9B	0.9600
Cu1—O1	2.1507 (18)	C9—H9C	0.9600
Cu1—Cu1ⁱ	2.6376 (6)	C2—C3	1.373 (4)
O5—C8	1.257 (3)	C2—H2A	0.9300
O2—C6	1.251 (3)	C4—C3	1.372 (4)
N1—O1	1.317 (3)	C4—H4A	0.9300
N1—C5	1.340 (3)	C3—H3A	0.9300
N1—C1	1.344 (3)	C7—H7A	0.9600
C8—C9	1.504 (3)	C7—H7B	0.9600
C6—C7	1.496 (3)	C7—H7C	0.9600

C6—O3—Cu1ⁱ	123.11 (16)	O3—C6—C7	117.3 (2)
C8—O4—Cu1ⁱ	126.30 (16)	N1—C1—C2	120.5 (2)
O5—Cu1—O2	89.09 (8)	N1—C1—H1A	119.7
O5—Cu1—O4ⁱ	167.89 (7)	C2—C1—H1A	119.7
O2—Cu1—O4ⁱ	89.45 (8)	N1—C5—C4	120.1 (2)
O5—Cu1—O3ⁱ	89.38 (8)	N1—C5—H5A	120.0
O2—Cu1—O3ⁱ	167.91 (7)	C4—C5—H5A	120.0
O4ⁱ—Cu1—O3ⁱ	89.55 (8)	C8—C9—H9A	109.5
O5—Cu1—O1	101.25 (8)	C8—C9—H9B	109.5
O2—Cu1—O1	90.70 (7)	H9A—C9—H9B	109.5
O4ⁱ—Cu1—O1	90.79 (8)	C8—C9—H9C	109.5
O3ⁱ—Cu1—O1	101.35 (7)	H9A—C9—H9C	109.5
O5—Cu1—Cu1ⁱ	86.37 (6)	H9B—C9—H9C	109.5
O2—Cu1—Cu1ⁱ	83.97 (5)	C1—C2—C3	120.3 (3)
O4ⁱ—Cu1—Cu1ⁱ	81.52 (5)	C1—C2—H2A	119.8
O3ⁱ—Cu1—Cu1ⁱ	83.97 (5)	C3—C2—H2A	119.8
O1—Cu1—Cu1ⁱ	170.66 (6)	C5—C4—C3	120.9 (3)
C8—O5—Cu1	120.79 (16)	C5—C4—H4A	119.6
C6—O2—Cu1	123.67 (16)	C3—C4—H4A	119.6
O1—N1—C5	117.7 (2)	C4—C3—C2	117.8 (3)
O1—N1—C1	121.9 (2)	C4—C3—H3A	121.1
C5—N1—C1	120.3 (2)	C2—C3—H3A	121.1
O4—C8—O5	124.9 (2)	C6—C7—H7A	109.5
O4—C8—C9	117.0 (2)	C6—C7—H7B	109.5
O5—C8—C9	118.0 (2)	H7A—C7—H7B	109.5
N1—O1—Cu1	134.01 (15)	C6—C7—H7C	109.5
O2—C6—O3	125.2 (2)	H7A—C7—H7C	109.5
O2—C6—C7	117.5 (2)	H7B—C7—H7C	109.5

O2—Cu1—O5—C8	82.77 (19)	O5—Cu1—O1—N1	76.0 (2)
O4ⁱ—Cu1—O5—C8	−0.3 (5)	O2—Cu1—O1—N1	165.2 (2)
O3ⁱ—Cu1—O5—C8	−85.24 (19)	O4ⁱ—Cu1—O1—N1	−105.3 (2)
O1—Cu1—O5—C8	173.30 (19)	O3ⁱ—Cu1—O1—N1	−15.6 (3)
Cu1ⁱ—Cu1—O5—C8	−1.25 (18)	Cu1—O2—C6—O3	1.9 (4)
O5—Cu1—O2—C6	−88.0 (2)	Cu1—O2—C6—C7	−178.14 (19)
O4ⁱ—Cu1—O2—C6	79.9 (2)	Cu1ⁱ—O3—C6—O2	−0.8 (4)
O3ⁱ—Cu1—O2—C6	−5.3 (5)	Cu1ⁱ—O3—C6—C7	179.25 (19)
O1—Cu1—O2—C6	170.7 (2)	O1—N1—C1—C2	−179.5 (2)
Cu1ⁱ—Cu1—O2—C6	−1.59 (19)	C5—N1—C1—C2	0.0 (4)
Cu1ⁱ—O4—C8—O5	−3.5 (4)	O1—N1—C5—C4	179.2 (3)
Cu1ⁱ—O4—C8—C9	175.76 (18)	C1—N1—C5—C4	−0.3 (4)
Cu1—O5—C8—O4	3.1 (3)	N1—C1—C2—C3	0.1 (4)
Cu1—O5—C8—C9	−176.22 (18)	N1—C5—C4—C3	0.5 (5)
C5—N1—O1—Cu1	172.94 (19)	C5—C4—C3—C2	−0.3 (5)
C1—N1—O1—Cu1	−7.5 (4)	C1—C2—C3—C4	0.0 (5)

Symmetry code: (i) −x+1, −y, −z.

Experimental details

Crystal data
Chemical formula	[Cu₂(C₂H₃O₂)₄(C₅H₅NO)₂]
M_r	553.46
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	9.6737 (11), 13.5886 (16), 8.5236 (10)
β (°)	99.970 (2)
V (Å³)	1103.5 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.98
Crystal size (mm)	0.2 × 0.2 × 0.2

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 1998)
T_min, T_max	0.673, 0.680
No. of measured, independent and observed [I > 2σ(I)] reflections	5445, 1936, 1713
R_int	0.015
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.025, 0.070, 1.07
No. of reflections	1936
No. of parameters	145
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.43, −0.33

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

This work was supported by Beijing Municipal Natural Science Foundation (No. 2082004) and the Seventh Technology Fund for Postgraduates of Beijing University of Technology.

References

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