catena-Poly[[bis­(μ-5-bromo­pyridine-3-carboxyl­ato-κ2O:O′)dicopper(II)]-bis­(μ-5-bromo­pyridine-3-carboxyl­ato)-κ3O,O′:N;κ3N:O,O′]

DeBurgomaster, P.; Zubieta, J.

doi:10.1107/S160053681004242X

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 11| November 2010| Page m1459

https://doi.org/10.1107/S160053681004242X

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catena-Poly[[bis(μ-5-bromopyridine-3-carboxylato-κ²O:O′)dicopper(II)]-bis(μ-5-bromopyridine-3-carboxylato)-κ³O,O′:N;κ³N:O,O′]

Paul DeBurgomaster ^a and Jon Zubieta ^a ^*

^aDepartment of Chemistry, Syracuse University, Syracuse, New York 13244, USA
^*Correspondence e-mail: jazubiet@syr.edu

(Received 7 October 2010; accepted 19 October 2010; online 23 October 2010)

The title compound [Cu₂(C₆H₃BrNO₂)₄]_n, forms sheets in the bc plane. The structure features the dinuclear paddle-wheel cage motif common to copper(II) carboxylates. The polymeric structure is achieved through bridging between binuclear units by the pyridyl donors of two of the four carboxylates of the cage. Each cage engages in axial bonding at each copper atom to a pyridyl nitrogen donor and extends two 5-bromopyridine-3-carboxylate groups to bridge to adjacent binuclear sites in the bc plane. Each cage is linked to four adjacent cages in the plane. The intradimer Cu⋯Cu distance is 2.6465 (5) Å. The remaining 5-bromopyridine-3-carboxylate groups project into the interlamellar domain and interdigitate in pairs from each neighboring layer.

Related literature

For a general review of copper(II) carboxylates, see: Doedens (1976 ). For polynuclear copper carboxylates with the [Cu₂(O₂CR)₄] core, see: Agterberg et al. (1997 ); Valentine et al. (1974 ); Yamanaka et al. (1991 ). For the preparation of copper coordination polymers under hydrothermal conditions, see: Lu (2003 ). For general discussion of hydrothermal methods, see: Gopalakrishnan (1995 ); Zubieta (2004 ).

Experimental

Crystal data

[Cu₂(C₆H₃BrNO₂)₄]
M_r = 931.11
Monoclinic, P 2₁ /n
a = 11.1390 (12) Å
b = 11.5866 (13) Å
c = 12.6325 (14) Å
β = 115.432 (2)°
V = 1472.4 (3) Å³
Z = 2
Mo Kα radiation
μ = 6.93 mm⁻¹
T = 90 K
0.35 × 0.30 × 0.27 mm

Data collection

Bruker APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1998 ) T_min = 0.196, T_max = 0.256
14281 measured reflections
3571 independent reflections
3218 reflections with I > 2σ(I)
R_int = 0.022

Refinement

R[F² > 2σ(F²)] = 0.021
wR(F²) = 0.054
S = 1.05
3571 reflections
190 parameters
H-atom parameters constrained
Δρ_max = 0.77 e Å⁻³
Δρ_min = −0.51 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: DIAMOND (Brandenburg & Putz, 1999 ); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S160053681004242X/rn2072sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053681004242X/rn2072Isup2.hkl

checkCIF report

Comment top

The dinuclear paddle-wheel cage structure of copper(II) carboxylates is well established [Doedens (1976)]. Polymeric structures incorporating this core can be obtained using ligands capable of bridging between the dinuclear units [Agterberg, et al. (1997); Valentine, et al. (1974); Yamanaka, et al. (1991)]. Since hydrothermal methods are most effective for the preparation and crystallization of organic-inorganic coordination polymers [Gopalakrishnan (1995); Zubieta (2004)], the crystal engineering of copper-containing materials under these conditions has witnessed considerable contemporary attention [Lu (2003)]. In the course of our investigations of Cu(II)-ligand substructures in complex metal oxide hybrid materials, the two-dimensional material [Cu₂(O₂CC₅H₃NBr)₄] was isolated.

As shown in Fig. 1, the title compound is two-dimensional, forming sheets oriented parallel to the crystallographic bc plane. The fundamental building block of these sheets is the dinuclear paddle-wheel cage structure [Cu₂(O₂CR)₄], shown in Fig. 2. The four oxygen donors of the basal plane about the crystallographically unique copper site exhibit Cu—O distances in the range of 1.959 (1)Å to 1.985 (1) Å. There is a crystallographic inversion center at the mid-point of the CuLCu vector relating the two halves of the cage. The Cu···Cu distance is 2.6465 (5) Å.

The cages are linked into the two-dimensional network through the pyridylnitrogen donors of two of the 5-bromopyridine-3-carboxylato ligands, with a copper-axial nitrogen distance of 2.160 (2) Å. The connectivity pattern links each [Cu₂(O₂CR)₄] cage to four neighboring cages to provide the 2-D extension. Two 5-bromopyridine-3-carboxylato ligands of each cage are pendant and project from either face of the polymeric sheets into the interlamellar domains (Fig. 3). These projecting groups interdigitate in pairs with those of neighboring sheets to provide a relatively densely packed arrangement of sheets.

Related literature top

For a general review of copper(II) carboxylates, see: Doedens (1976). For polynuclear copper carboxylates with the [Cu₂(O₂CR)₄] core, see: Agterberg, et al. (1997); Valentine, et al. (1974); Yamanaka, et al. (1991). For the preparation of copper coordination polymers under hydrothermal conditions, see: Lu (2003). For general discussion of hydrothermal methods, see: Gopalakrishnan (1995); Zubieta (2004).

Experimental top

A solution containing Cu(II) acetate hydrate (0.201 g, 1.01 mmol), 5-bromo-2-pyridylcarboxylic acid (0.102, 0.50 mmol), methanol (5.00 ml, 123.56 mmol), and DMF (5.00 ml, 64.58 mmol), in the mole ratio 2.02:1.00:247:129 was stirred briefly before transfer to a 20 ml glass vial. The capped vial was heated at 75 ^oC for 72 h. Green blocks of the title compound, suitable for X-ray diffraction, were isolated in 50% yield. Initial and final pH values of 4.0 and 4.0, respectively, were recorded. Anal. Calcd. for C₁₂H₆Br₂CuN₂O₄:C, 30.9; H, 1.29; N, 6.01. Found: C, 29.7; H, 1.55; N, 5.93.

Structure description top

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: DIAMOND (Brandenburg & Putz, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. A view of the two-dimensional structure of [Cu₂(O₂CC₅H₃NBr)₄] in the bc plane. Color scheme as for Fig. 2.
	Fig. 2. An ORTEP view of the dinuclear paddle-wheel cage building block of the title compound, showing the atom-labeling scheme for the asymmetric unit and 50% displacement ellipsoids. Color scheme: Cu, blue; Br, maroon; O, red; N, light blue; C, black; H, pink.
	Fig. 3. A view of the packing showing the interdigitation of the pendant 5-bromo-2-pyridyl groups. Color scheme as for Fig. 2.

catena-Poly[[bis(µ-5-bromopyridine-3-carboxylato- κ²O:O')dicopper(II)]-bis(µ-5-bromopyridine-3-carboxylato)- κ³O,O':N;κ³N:O,O'] top

Crystal data top

[Cu₂(C₆H₃BrNO₂)₄]	F(000) = 892
M_r = 931.11	D_x = 2.100 Mg m⁻³ D_m = 2.09 (2) Mg m⁻³ D_m measured by flotation
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 3266 reflections
a = 11.1390 (12) Å	θ = 2.4–28.3°
b = 11.5866 (13) Å	µ = 6.93 mm⁻¹
c = 12.6325 (14) Å	T = 90 K
β = 115.432 (2)°	Block, blue
V = 1472.4 (3) Å³	0.35 × 0.30 × 0.27 mm
Z = 2

Data collection top

Bruker APEX CCD area-detector diffractometer	3571 independent reflections
Radiation source: fine-focus sealed tube	3218 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.022
Detector resolution: 512 pixels mm^-1	θ_max = 28.1°, θ_min = 2.0°
φ and ω scans	h = −14→14
Absorption correction: multi-scan (SADABS; Bruker, 1998)	k = −15→14
T_min = 0.196, T_max = 0.256	l = −15→16
14281 measured reflections

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)] = 0.021	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.054	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0258P)² + 1.3076P] where P = (F_o² + 2F_c²)/3
3571 reflections	(Δ/σ)_max = 0.001
190 parameters	Δρ_max = 0.77 e Å⁻³
0 restraints	Δρ_min = −0.51 e Å⁻³

Crystal data top

[Cu₂(C₆H₃BrNO₂)₄]	V = 1472.4 (3) Å³
M_r = 931.11	Z = 2
Monoclinic, P2₁/n	Mo Kα radiation
a = 11.1390 (12) Å	µ = 6.93 mm⁻¹
b = 11.5866 (13) Å	T = 90 K
c = 12.6325 (14) Å	0.35 × 0.30 × 0.27 mm
β = 115.432 (2)°

Data collection top

Bruker APEX CCD area-detector diffractometer	3571 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1998)	3218 reflections with I > 2σ(I)
T_min = 0.196, T_max = 0.256	R_int = 0.022
14281 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.021	0 restraints
wR(F²) = 0.054	H-atom parameters constrained
S = 1.05	Δρ_max = 0.77 e Å⁻³
3571 reflections	Δρ_min = −0.51 e Å⁻³
190 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
Br1	−0.18056 (2)	0.76143 (2)	−0.11231 (2)	0.02559 (7)
Br2	0.84249 (2)	0.868086 (18)	0.603257 (19)	0.02064 (6)
Cu1	0.56886 (2)	1.02600 (2)	0.11208 (2)	0.01009 (6)
O1	0.40781 (14)	0.98221 (13)	0.12844 (14)	0.0179 (3)
O2	0.29176 (14)	0.93567 (13)	−0.06153 (13)	0.0174 (3)
O3	1.00043 (14)	1.31393 (12)	0.57312 (13)	0.0153 (3)
O4	0.88355 (15)	1.36151 (12)	0.38361 (13)	0.0176 (3)
N1	0.08987 (19)	0.89646 (18)	0.19994 (17)	0.0232 (4)
N2	0.70137 (17)	1.05035 (15)	0.29489 (15)	0.0142 (3)
C1	−0.0161 (2)	0.8474 (2)	0.1151 (2)	0.0214 (5)
H1	−0.0875	0.8233	0.1320	0.026*
C2	−0.0258 (2)	0.83017 (19)	0.00277 (19)	0.0176 (4)
C3	0.0770 (2)	0.86282 (17)	−0.0242 (2)	0.0161 (4)
H3	0.0718	0.8518	−0.1006	0.019*
C4	0.1886 (2)	0.91256 (18)	0.06474 (19)	0.0146 (4)
C5	0.1900 (2)	0.92849 (19)	0.17425 (19)	0.0181 (4)
H5	0.2657	0.9639	0.2340	0.022*
C6	0.30570 (19)	0.94647 (17)	0.04201 (19)	0.0139 (4)
C7	0.7262 (2)	0.96880 (18)	0.37741 (18)	0.0146 (4)
H7	0.6806	0.8971	0.3561	0.018*
C8	0.8166 (2)	0.98675 (17)	0.49263 (18)	0.0137 (4)
C9	0.8847 (2)	1.09039 (17)	0.52675 (18)	0.0138 (4)
H9	0.9470	1.1034	0.6056	0.017*
C10	0.85843 (19)	1.17443 (17)	0.44120 (18)	0.0116 (4)
C11	0.76676 (19)	1.15074 (17)	0.32653 (18)	0.0132 (4)
H11	0.7500	1.2083	0.2683	0.016*
C12	0.92049 (19)	1.29269 (17)	0.46889 (18)	0.0124 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.01981 (11)	0.03107 (13)	0.02547 (13)	−0.01189 (9)	0.00931 (10)	−0.00522 (10)
Br2	0.03049 (12)	0.01399 (11)	0.01496 (11)	−0.00414 (8)	0.00738 (9)	0.00332 (8)
Cu1	0.01025 (11)	0.00862 (12)	0.00980 (12)	0.00020 (8)	0.00280 (9)	0.00007 (9)
O1	0.0152 (7)	0.0211 (8)	0.0180 (8)	−0.0049 (6)	0.0078 (6)	−0.0028 (6)
O2	0.0140 (7)	0.0229 (8)	0.0163 (8)	−0.0013 (6)	0.0073 (6)	0.0000 (6)
O3	0.0183 (7)	0.0113 (7)	0.0127 (7)	−0.0035 (6)	0.0033 (6)	−0.0016 (6)
O4	0.0220 (8)	0.0105 (7)	0.0139 (8)	−0.0030 (6)	0.0015 (6)	0.0012 (6)
N1	0.0233 (10)	0.0302 (11)	0.0186 (10)	−0.0033 (8)	0.0113 (8)	0.0015 (8)
N2	0.0163 (8)	0.0120 (8)	0.0130 (9)	−0.0012 (6)	0.0049 (7)	−0.0006 (7)
C1	0.0197 (10)	0.0245 (11)	0.0239 (12)	−0.0031 (9)	0.0130 (9)	0.0016 (9)
C2	0.0142 (9)	0.0171 (10)	0.0201 (11)	−0.0033 (8)	0.0060 (8)	−0.0010 (9)
C3	0.0176 (10)	0.0140 (10)	0.0184 (11)	0.0002 (8)	0.0092 (8)	0.0003 (8)
C4	0.0143 (9)	0.0124 (9)	0.0175 (10)	0.0008 (7)	0.0073 (8)	0.0024 (8)
C5	0.0169 (10)	0.0190 (11)	0.0170 (11)	−0.0025 (8)	0.0060 (8)	0.0001 (8)
C6	0.0132 (9)	0.0090 (9)	0.0197 (11)	0.0008 (7)	0.0071 (8)	0.0017 (8)
C7	0.0168 (10)	0.0119 (9)	0.0151 (10)	−0.0038 (7)	0.0068 (8)	−0.0024 (8)
C8	0.0174 (9)	0.0116 (9)	0.0125 (10)	0.0005 (7)	0.0068 (8)	0.0038 (8)
C9	0.0145 (9)	0.0143 (10)	0.0115 (10)	−0.0005 (7)	0.0045 (8)	−0.0016 (8)
C10	0.0130 (9)	0.0094 (9)	0.0127 (10)	0.0000 (7)	0.0056 (7)	−0.0011 (7)
C11	0.0142 (9)	0.0114 (9)	0.0132 (10)	−0.0007 (7)	0.0053 (8)	0.0013 (7)
C12	0.0125 (9)	0.0107 (9)	0.0154 (10)	0.0004 (7)	0.0072 (8)	−0.0007 (8)

Geometric parameters (Å, º) top

Br1—C2	1.888 (2)	C1—C2	1.390 (3)
Br2—C8	1.892 (2)	C1—H1	0.9500
Cu1—O1	1.9588 (14)	C2—C3	1.380 (3)
Cu1—O2ⁱ	1.9665 (14)	C3—C4	1.393 (3)
Cu1—O4ⁱⁱ	1.9726 (14)	C3—H3	0.9500
Cu1—O3ⁱⁱⁱ	1.9852 (14)	C4—C5	1.389 (3)
Cu1—N2	2.1595 (18)	C4—C6	1.504 (3)
Cu1—Cu1ⁱ	2.6465 (5)	C5—H5	0.9500
O1—C6	1.261 (3)	C7—C8	1.384 (3)
O2—C6	1.255 (3)	C7—H7	0.9500
O3—C12	1.257 (2)	C8—C9	1.387 (3)
O4—C12	1.259 (2)	C9—C10	1.389 (3)
N1—C1	1.334 (3)	C9—H9	0.9500
N1—C5	1.340 (3)	C10—C11	1.395 (3)
N2—C11	1.339 (3)	C10—C12	1.507 (3)
N2—C7	1.345 (3)	C11—H11	0.9500

O1—Cu1—O2ⁱ	168.33 (6)	C2—C3—H3	121.2
O1—Cu1—O4ⁱⁱ	89.67 (6)	C4—C3—H3	121.2
O2ⁱ—Cu1—O4ⁱⁱ	89.25 (7)	C5—C4—C3	118.87 (19)
O1—Cu1—O3ⁱⁱⁱ	89.81 (6)	C5—C4—C6	121.06 (19)
O2ⁱ—Cu1—O3ⁱⁱⁱ	88.91 (6)	C3—C4—C6	120.06 (19)
O4ⁱⁱ—Cu1—O3ⁱⁱⁱ	168.37 (6)	N1—C5—C4	123.3 (2)
O1—Cu1—N2	99.05 (7)	N1—C5—H5	118.3
O2ⁱ—Cu1—N2	92.60 (6)	C4—C5—H5	118.3
O4ⁱⁱ—Cu1—N2	92.56 (6)	O2—C6—O1	126.63 (18)
O3ⁱⁱⁱ—Cu1—N2	99.00 (6)	O2—C6—C4	116.34 (18)
O1—Cu1—Cu1ⁱ	85.28 (5)	O1—C6—C4	117.03 (18)
O2ⁱ—Cu1—Cu1ⁱ	83.08 (5)	N2—C7—C8	121.60 (18)
O4ⁱⁱ—Cu1—Cu1ⁱ	80.50 (4)	N2—C7—H7	119.2
O3ⁱⁱⁱ—Cu1—Cu1ⁱ	87.88 (4)	C8—C7—H7	119.2
N2—Cu1—Cu1ⁱ	171.84 (5)	C7—C8—C9	120.71 (18)
C6—O1—Cu1	121.33 (13)	C7—C8—Br2	118.60 (15)
C6—O2—Cu1ⁱ	123.66 (13)	C9—C8—Br2	120.67 (16)
C12—O3—Cu1^iv	117.81 (13)	C8—C9—C10	117.44 (19)
C12—O4—Cu1^v	127.10 (14)	C8—C9—H9	121.3
C1—N1—C5	117.7 (2)	C10—C9—H9	121.3
C11—N2—C7	118.33 (18)	C9—C10—C11	119.06 (18)
C11—N2—Cu1	117.85 (14)	C9—C10—C12	122.30 (18)
C7—N2—Cu1	123.76 (14)	C11—C10—C12	118.57 (17)
N1—C1—C2	122.4 (2)	N2—C11—C10	122.86 (18)
N1—C1—H1	118.8	N2—C11—H11	118.6
C2—C1—H1	118.8	C10—C11—H11	118.6
C3—C2—C1	120.2 (2)	O3—C12—O4	126.62 (18)
C3—C2—Br1	120.35 (17)	O3—C12—C10	117.99 (18)
C1—C2—Br1	119.44 (15)	O4—C12—C10	115.38 (18)
C2—C3—C4	117.5 (2)

O2ⁱ—Cu1—O1—C6	5.4 (4)	Cu1—O1—C6—C4	178.63 (13)
O4ⁱⁱ—Cu1—O1—C6	−79.30 (16)	C5—C4—C6—O2	−175.55 (19)
O3ⁱⁱⁱ—Cu1—O1—C6	89.08 (16)	C3—C4—C6—O2	5.4 (3)
N2—Cu1—O1—C6	−171.84 (15)	C5—C4—C6—O1	4.8 (3)
Cu1ⁱ—Cu1—O1—C6	1.20 (15)	C3—C4—C6—O1	−174.31 (19)
O1—Cu1—N2—C11	−127.00 (15)	C11—N2—C7—C8	0.1 (3)
O2ⁱ—Cu1—N2—C11	53.57 (15)	Cu1—N2—C7—C8	177.04 (15)
O4ⁱⁱ—Cu1—N2—C11	142.93 (15)	N2—C7—C8—C9	0.1 (3)
O3ⁱⁱⁱ—Cu1—N2—C11	−35.75 (15)	N2—C7—C8—Br2	178.81 (15)
O1—Cu1—N2—C7	56.05 (17)	C7—C8—C9—C10	0.1 (3)
O2ⁱ—Cu1—N2—C7	−123.39 (16)	Br2—C8—C9—C10	−178.61 (14)
O4ⁱⁱ—Cu1—N2—C7	−34.03 (16)	C8—C9—C10—C11	−0.4 (3)
O3ⁱⁱⁱ—Cu1—N2—C7	147.30 (16)	C8—C9—C10—C12	176.54 (18)
C5—N1—C1—C2	−0.7 (3)	C7—N2—C11—C10	−0.5 (3)
N1—C1—C2—C3	0.8 (4)	Cu1—N2—C11—C10	−177.61 (15)
N1—C1—C2—Br1	−179.34 (18)	C9—C10—C11—N2	0.7 (3)
C1—C2—C3—C4	0.1 (3)	C12—C10—C11—N2	−176.43 (18)
Br1—C2—C3—C4	−179.72 (15)	Cu1^iv—O3—C12—O4	4.0 (3)
C2—C3—C4—C5	−1.1 (3)	Cu1^iv—O3—C12—C10	−174.39 (12)
C2—C3—C4—C6	178.03 (19)	Cu1^v—O4—C12—O3	−3.7 (3)
C1—N1—C5—C4	−0.3 (3)	Cu1^v—O4—C12—C10	174.71 (12)
C3—C4—C5—N1	1.2 (3)	C9—C10—C12—O3	1.3 (3)
C6—C4—C5—N1	−177.9 (2)	C11—C10—C12—O3	178.26 (18)
Cu1ⁱ—O2—C6—O1	−0.2 (3)	C9—C10—C12—O4	−177.28 (18)
Cu1ⁱ—O2—C6—C4	−179.81 (13)	C11—C10—C12—O4	−0.3 (3)
Cu1—O1—C6—O2	−1.0 (3)

Symmetry codes: (i) −x+1, −y+2, −z; (ii) −x+3/2, y−1/2, −z+1/2; (iii) x−1/2, −y+5/2, z−1/2; (iv) x+1/2, −y+5/2, z+1/2; (v) −x+3/2, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	[Cu₂(C₆H₃BrNO₂)₄]
M_r	931.11
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	90
a, b, c (Å)	11.1390 (12), 11.5866 (13), 12.6325 (14)
β (°)	115.432 (2)
V (Å³)	1472.4 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	6.93
Crystal size (mm)	0.35 × 0.30 × 0.27

Data collection
Diffractometer	Bruker APEX CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 1998)
T_min, T_max	0.196, 0.256
No. of measured, independent and observed [I > 2σ(I)] reflections	14281, 3571, 3218
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.662

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.021, 0.054, 1.05
No. of reflections	3571
No. of parameters	190
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.77, −0.51

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg & Putz, 1999), SHELXTL (Sheldrick, 2008).

Acknowledgements

This work was supported by a grant from the National Science Foundation, CHE-0907787.

References

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