Tetra-μ3-iodido-tetra­kis­{[ethyl 2-(1H-benzimidazol-1-yl)acetate-κN3]copper(I)}

Yang, L.; Zhang, Z.

doi:10.1107/S160053681202257X

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 6| June 2012| Page m796

doi:10.1107/S160053681202257X

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Tetra-μ₃-iodido-tetrakis{[ethyl 2-(1H-benzimidazol-1-yl)acetate-κN³]copper(I)}

Lili Yang ^a ^* and Zhengyi Zhang ^a

^aDepartment of General Medicine, Lanzhou University Second Hospital, Lanzhou 730030, People's Republic of China
^*Correspondence e-mail: llyang666@163.com

(Received 9 May 2012; accepted 17 May 2012; online 26 May 2012)

The complex molecule of the tetranuclear cubane-type title compound, [Cu₄I₄(C₁₁H₁₂N₂O₂)₄], has crystallographically imposed fourfold inversion symmetry. The Cu^I ions are coordinated in a distorted tetrahedral geometry by an N atom of a benzimidazole ring system and three μ₃-iodide ions, forming a Cu₄I₄ core. In the crystal, complex molecules are connected into a three-dimensional network by C—H⋯O hydrogen bonds involving H and O atoms of adjacent ethoxycarbonyl groups.

Related literature

For potential applications in physiological and pharmacological fields of benzimidazoyl derivatives or complexes based on the benzimidazoyl unit, see: Ramla et al. (2007 ); Barreca et al. (2007 ); Cetinkaya et al. (1999 ); Snyderwine et al. (1997 ); Skog & Solyakov (2002 ); Garner et al. (1999 ). For applications of copper complexes in biology or medicine, see: Sorrell 1989 . For related structures, see: Sun et al. (2011 ); Liu et al. (2011 ); Toth et al. (1987 ).

Experimental

Crystal data

[Cu₄I₄(C₁₁H₁₂N₂O₂)₄]
M_r = 1578.66
Tetragonal, I 4₁ /a
a = 21.196 (11) Å
c = 11.581 (7) Å
V = 5203 (5) Å³
Z = 4
Mo Kα radiation
μ = 4.04 mm⁻¹
T = 296 K
0.24 × 0.22 × 0.18 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2007 ) T_min = 0.768, T_max = 0.784
13042 measured reflections
2422 independent reflections
2018 reflections with I > 2σ(I)
R_int = 0.046

Refinement

R[F² > 2σ(F²)] = 0.023
wR(F²) = 0.053
S = 1.03
2422 reflections
155 parameters
H-atom parameters constrained
Δρ_max = 0.35 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C10—H10A⋯O1ⁱ	0.97	2.60	3.531 (5)	162
Symmetry code: (i) $[y-{\script{1\over 4}}, -x+{\script{7\over 4}}, z-{\script{1\over 4}}]$ .

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); 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 I, global. DOI: 10.1107/S160053681202257X/rz2757sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681202257X/rz2757Isup2.hkl

checkCIF report

Comment top

Benzimidazoyl-based ligands have wide applications in physiological and pharmacological fields, such as treatment of hypoglycemia, inhibitory activity for the lymphoma of Burkitt, antimicrobial activity and other effects (Ramla et al., 2007; Barreca et al., 2007; Cetinkaya et al., 1999). Similarly, some metal complexes of benzimidazoyl derivatives possess interesting activities such as anti-viral, anti-cancers and anti-fungal activities (Snyderwine et al., 1997; Skog & Solyakov,2002; Garner et al., 1999). In particular, copper complexes are often used as chemical models of copper proteins and copper enzymes (Sorrell, 1989). Up to now, a number of structures of copper complexes involving the benzimidazol group have been reported (Sun et al., 2011; Liu et al., 2011; Toth et al., 1987), but no crystal structure of copper(I) complex based on ethyl 2-(1H- benzimidazol-1-yl)acetate is available. In order to contribute to this research field, we report herein the crystal structure of the title tetranuclear cubane-type complex.

In the title complex (Fig. 1), each copper(I) metal of the Cu₄I₄ core is coordinated by three µ₃-iodide ions and a nitrogen atom of a benzimidazole ring system in a distorted tetrahedral geometry. The deviation from the ideal geometry can be indicated by the range [104.30 (9)–114.311 (17) °] of the bond angles around the metal. The Cu—N bond length is 2.038 (3) Å, and the Cu—I bond lengths fall in the range are 2.715 (14)–2.733 (14) %A. In the crystal structure (Fig. 2), complex molecules are connected into a three-dimensional network by C—H···O hydrogen bonds (Table 1) involving H and O atoms of adjacent ethyl acetate groups.

Related literature top

For potential applications in physiological and pharmacological fields of benzimidazoyl derivatives or complexes based on the benzimidazoyl unit, see: Ramla et al. (2007); Barreca et al. (2007); Cetinkaya et al. (1999); Snyderwine et al. (1997); Skog & Solyakov (2002); Garner et al. (1999). For applications of copper complexes in biology or medicine, see: Sorrell 1989. For related structures, see: Sun et al. (2011); Liu et al. (2011); Toth et al. (1987).

Experimental top

A mixture of ethyl 2-(1H-benzimidazol-1-yl)acetate (0.015 g, 0.1 mmol), CuI (0.019 g, 0.1 mmol), 3 mL H₂O and 10 mL EtOH was heated at 160°C under hydrothermal condition in a Teflon lined steel autoclave (inner volume 15 mL) for 3 days, and then cooled to room temperature at a rate of 2°C h^-1. Red single crystals suitable for X-Ray diffraction were obtained in 43% yield. Elemental Calc. for C₄₄H₄₈Cu₄I₄N₈O₈: C, 33.48; H, 3.06; N, 7.10%. Found: C, 33.61; H, 3.21; N, 7.21%.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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. The structure of the title complex with displacement ellipsoids drawn at the 30% probability level. Atoms labelled with suffix A, B and C are generated by the symmetry operator (2-x, 1.5-y, z), (0.25+y, 1.75-x, 0.75-z) and (1.75-y, -0.25+x, 0.75-z) respectively.
	Fig. 2. Packing diagram of the title compound viewed along the c axis.

Tetra-µ₃-iodido-tetrakis{[ethyl 2-(1H-benzimidazol-1-yl)acetate-κN³]copper(I)} top

Crystal data top

[Cu₄I₄(C₁₁H₁₂N₂O₂)₄]	D_x = 2.015 Mg m⁻³
M_r = 1578.66	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I4₁/a	Cell parameters from 4922 reflections
Hall symbol: -I 4ad	θ = 2.7–27.9°
a = 21.196 (11) Å	µ = 4.04 mm⁻¹
c = 11.581 (7) Å	T = 296 K
V = 5203 (5) Å³	Block, red
Z = 4	0.24 × 0.22 × 0.18 mm
F(000) = 3040

Data collection top

Bruker APEXII CCD diffractometer	2422 independent reflections
Radiation source: fine-focus sealed tube	2018 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.046
ϕ and ω scans	θ_max = 25.5°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −14→25
T_min = 0.768, T_max = 0.784	k = −25→24
13042 measured reflections	l = −13→14

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)] = 0.023	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.053	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0216P)² + 3.0196P] where P = (F_o² + 2F_c²)/3
2422 reflections	(Δ/σ)_max = 0.004
155 parameters	Δρ_max = 0.35 e Å⁻³
0 restraints	Δρ_min = −0.32 e Å⁻³

Crystal data top

[Cu₄I₄(C₁₁H₁₂N₂O₂)₄]	Z = 4
M_r = 1578.66	Mo Kα radiation
Tetragonal, I4₁/a	µ = 4.04 mm⁻¹
a = 21.196 (11) Å	T = 296 K
c = 11.581 (7) Å	0.24 × 0.22 × 0.18 mm
V = 5203 (5) Å³

Data collection top

Bruker APEXII CCD diffractometer	2422 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2007)	2018 reflections with I > 2σ(I)
T_min = 0.768, T_max = 0.784	R_int = 0.046
13042 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.023	0 restraints
wR(F²) = 0.053	H-atom parameters constrained
S = 1.03	Δρ_max = 0.35 e Å⁻³
2422 reflections	Δρ_min = −0.32 e Å⁻³
155 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
I1	1.102882 (10)	0.771393 (11)	0.517267 (18)	0.04331 (9)
O2	0.78785 (12)	1.08340 (12)	0.5233 (2)	0.0575 (7)
C9	0.81754 (17)	1.02891 (18)	0.5439 (3)	0.0471 (9)
C11	0.7103 (2)	1.1347 (3)	0.4120 (7)	0.143 (3)
H11A	0.7103	1.1719	0.4593	0.214*
H11B	0.6699	1.1302	0.3753	0.214*
H11C	0.7425	1.1383	0.3541	0.214*
C8	0.88524 (16)	1.04277 (16)	0.5783 (3)	0.0506 (9)
H8A	0.9052	1.0679	0.5186	0.061*
H8B	0.8855	1.0671	0.6493	0.061*
C10	0.72251 (18)	1.0806 (2)	0.4824 (4)	0.0664 (11)
H10A	0.7160	1.0424	0.4379	0.080*
H10B	0.6939	1.0800	0.5477	0.080*
O1	0.79545 (12)	0.97762 (12)	0.5333 (2)	0.0598 (7)
N2	0.92099 (13)	0.98507 (12)	0.5952 (2)	0.0443 (7)
N1	0.96375 (13)	0.89215 (13)	0.5503 (2)	0.0435 (7)
C7	0.93802 (16)	0.94424 (16)	0.5110 (3)	0.0440 (8)
H7	0.9321	0.9523	0.4328	0.053*
C5	0.93545 (16)	0.95618 (15)	0.7004 (3)	0.0428 (8)
C6	0.96267 (15)	0.89832 (15)	0.6711 (3)	0.0405 (8)
C4	0.92889 (18)	0.97605 (18)	0.8156 (3)	0.0556 (10)
H4	0.9111	1.0148	0.8347	0.067*
C3	0.95049 (19)	0.9346 (2)	0.8988 (3)	0.0626 (11)
H3	0.9472	0.9457	0.9762	0.075*
C1	0.98362 (18)	0.85733 (18)	0.7569 (3)	0.0538 (10)
H1	1.0014	0.8185	0.7385	0.065*
C2	0.97706 (18)	0.87645 (19)	0.8701 (3)	0.0603 (10)
H2	0.9907	0.8499	0.9289	0.072*
Cu1	0.98756 (2)	0.81434 (2)	0.45656 (4)	0.04928 (13)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
I1	0.03946 (14)	0.04686 (15)	0.04360 (13)	−0.00175 (11)	−0.00630 (9)	−0.00031 (10)
O2	0.0476 (15)	0.0452 (15)	0.0798 (18)	0.0054 (13)	−0.0103 (13)	0.0033 (13)
C9	0.047 (2)	0.047 (2)	0.0474 (19)	0.003 (2)	0.0016 (17)	−0.0051 (17)
C11	0.068 (3)	0.104 (4)	0.256 (9)	0.012 (4)	−0.033 (4)	0.080 (5)
C8	0.047 (2)	0.0350 (19)	0.070 (2)	0.0048 (18)	−0.0008 (18)	−0.0054 (17)
C10	0.050 (2)	0.074 (3)	0.076 (3)	0.004 (2)	−0.011 (2)	0.006 (2)
O1	0.0576 (17)	0.0428 (15)	0.0789 (18)	−0.0059 (14)	−0.0057 (14)	−0.0100 (13)
N2	0.0445 (17)	0.0343 (15)	0.0542 (17)	0.0042 (14)	−0.0006 (14)	−0.0027 (13)
N1	0.0467 (17)	0.0391 (16)	0.0446 (15)	0.0054 (14)	−0.0011 (13)	−0.0027 (13)
C7	0.042 (2)	0.043 (2)	0.0469 (19)	0.0004 (17)	−0.0031 (16)	−0.0032 (16)
C5	0.0369 (18)	0.042 (2)	0.049 (2)	−0.0038 (16)	0.0005 (16)	−0.0007 (16)
C6	0.0400 (19)	0.0360 (18)	0.0456 (18)	0.0006 (16)	0.0008 (15)	−0.0037 (15)
C4	0.057 (2)	0.053 (2)	0.058 (2)	0.002 (2)	0.0094 (19)	−0.0157 (19)
C3	0.071 (3)	0.074 (3)	0.043 (2)	−0.002 (2)	0.0065 (19)	−0.007 (2)
C1	0.062 (3)	0.044 (2)	0.055 (2)	0.003 (2)	−0.0007 (18)	0.0030 (17)
C2	0.068 (3)	0.062 (3)	0.051 (2)	−0.001 (2)	0.001 (2)	0.009 (2)
Cu1	0.0551 (3)	0.0414 (2)	0.0513 (3)	0.0049 (2)	0.0002 (2)	−0.0078 (2)

Geometric parameters (Å, º) top

I1—Cu1	2.7015 (14)	N1—C6	1.406 (4)
I1—Cu1ⁱ	2.7244 (16)	N1—Cu1	2.038 (3)
I1—Cu1ⁱⁱ	2.7334 (14)	C7—H7	0.9300
O2—C9	1.337 (4)	C5—C6	1.397 (4)
O2—C10	1.465 (4)	C5—C4	1.406 (5)
C9—O1	1.190 (4)	C6—C1	1.392 (5)
C9—C8	1.518 (5)	C4—C3	1.383 (5)
C11—C10	1.432 (6)	C4—H4	0.9300
C11—H11A	0.9600	C3—C2	1.395 (5)
C11—H11B	0.9600	C3—H3	0.9300
C11—H11C	0.9600	C1—C2	1.379 (5)
C10—H10A	0.9700	C1—H1	0.9300
C10—H10B	0.9700	C2—H2	0.9300
C8—N2	1.452 (4)	Cu1—I1ⁱⁱⁱ	2.7244 (16)
C8—H8A	0.9700	Cu1—Cu1ⁱⁱⁱ	2.7252 (13)
C8—H8B	0.9700	Cu1—Cu1ⁱ	2.7252 (13)
N2—C7	1.353 (4)	Cu1—I1ⁱⁱ	2.7334 (14)
N2—C5	1.397 (4)	Cu1—Cu1ⁱⁱ	2.7780 (17)
N1—C7	1.313 (4)

Cu1—I1—Cu1ⁱ	60.299 (15)	C1—C6—C5	120.5 (3)
Cu1—I1—Cu1ⁱⁱ	61.477 (17)	C1—C6—N1	130.3 (3)
Cu1ⁱ—I1—Cu1ⁱⁱ	59.912 (15)	C5—C6—N1	109.3 (3)
C9—O2—C10	117.9 (3)	C3—C4—C5	116.0 (3)
O1—C9—O2	125.9 (3)	C3—C4—H4	122.0
O1—C9—C8	125.1 (3)	C5—C4—H4	122.0
O2—C9—C8	108.9 (3)	C4—C3—C2	122.0 (4)
C10—C11—H11A	109.5	C4—C3—H3	119.0
C10—C11—H11B	109.5	C2—C3—H3	119.0
H11A—C11—H11B	109.5	C2—C1—C6	117.5 (3)
C10—C11—H11C	109.5	C2—C1—H1	121.2
H11A—C11—H11C	109.5	C6—C1—H1	121.2
H11B—C11—H11C	109.5	C1—C2—C3	121.8 (4)
N2—C8—C9	111.5 (3)	C1—C2—H2	119.1
N2—C8—H8A	109.3	C3—C2—H2	119.1
C9—C8—H8A	109.3	N1—Cu1—I1	110.98 (8)
N2—C8—H8B	109.3	N1—Cu1—I1ⁱⁱⁱ	104.30 (9)
C9—C8—H8B	109.3	I1—Cu1—I1ⁱⁱⁱ	114.311 (17)
H8A—C8—H8B	108.0	N1—Cu1—Cu1ⁱⁱⁱ	138.82 (8)
C11—C10—O2	108.8 (4)	I1—Cu1—Cu1ⁱⁱⁱ	110.146 (17)
C11—C10—H10A	109.9	I1ⁱⁱⁱ—Cu1—Cu1ⁱⁱⁱ	59.43 (4)
O2—C10—H10A	109.9	N1—Cu1—Cu1ⁱ	147.54 (8)
C11—C10—H10B	109.9	I1—Cu1—Cu1ⁱ	60.27 (4)
O2—C10—H10B	109.9	I1ⁱⁱⁱ—Cu1—Cu1ⁱ	60.21 (4)
H10A—C10—H10B	108.3	Cu1ⁱⁱⁱ—Cu1—Cu1ⁱ	61.29 (3)
C7—N2—C5	106.8 (3)	N1—Cu1—I1ⁱⁱ	103.14 (8)
C7—N2—C8	125.5 (3)	I1—Cu1—I1ⁱⁱ	110.098 (19)
C5—N2—C8	126.9 (3)	I1ⁱⁱⁱ—Cu1—I1ⁱⁱ	113.280 (17)
C7—N1—C6	105.1 (3)	Cu1ⁱⁱⁱ—Cu1—I1ⁱⁱ	59.88 (4)
C7—N1—Cu1	126.8 (2)	Cu1ⁱ—Cu1—I1ⁱⁱ	109.193 (17)
C6—N1—Cu1	127.6 (2)	N1—Cu1—Cu1ⁱⁱ	147.30 (8)
N1—C7—N2	113.5 (3)	I1—Cu1—Cu1ⁱⁱ	59.827 (16)
N1—C7—H7	123.2	I1ⁱⁱⁱ—Cu1—Cu1ⁱⁱ	107.917 (17)
N2—C7—H7	123.2	Cu1ⁱⁱⁱ—Cu1—Cu1ⁱⁱ	59.357 (16)
C6—C5—N2	105.3 (3)	Cu1ⁱ—Cu1—Cu1ⁱⁱ	59.357 (16)
C6—C5—C4	122.3 (3)	I1ⁱⁱ—Cu1—Cu1ⁱⁱ	58.696 (16)
N2—C5—C4	132.4 (3)

C10—O2—C9—O1	−0.9 (5)	C5—C6—C1—C2	−0.7 (5)
C10—O2—C9—C8	176.7 (3)	N1—C6—C1—C2	179.2 (3)
O1—C9—C8—N2	1.1 (5)	C6—C1—C2—C3	0.0 (6)
O2—C9—C8—N2	−176.6 (3)	C4—C3—C2—C1	0.4 (6)
C9—O2—C10—C11	−150.6 (4)	C7—N1—Cu1—I1	135.7 (3)
C9—C8—N2—C7	68.8 (4)	C6—N1—Cu1—I1	−54.4 (3)
C9—C8—N2—C5	−100.2 (4)	C7—N1—Cu1—I1ⁱⁱⁱ	12.1 (3)
C6—N1—C7—N2	1.2 (4)	C6—N1—Cu1—I1ⁱⁱⁱ	−177.9 (3)
Cu1—N1—C7—N2	173.0 (2)	C7—N1—Cu1—Cu1ⁱⁱⁱ	−47.5 (3)
C5—N2—C7—N1	−1.7 (4)	C6—N1—Cu1—Cu1ⁱⁱⁱ	122.5 (2)
C8—N2—C7—N1	−172.6 (3)	C7—N1—Cu1—Cu1ⁱ	68.4 (3)
C7—N2—C5—C6	1.5 (3)	C6—N1—Cu1—Cu1ⁱ	−121.6 (3)
C8—N2—C5—C6	172.1 (3)	C7—N1—Cu1—I1ⁱⁱ	−106.4 (3)
C7—N2—C5—C4	179.3 (4)	C6—N1—Cu1—I1ⁱⁱ	63.5 (3)
C8—N2—C5—C4	−10.0 (6)	C7—N1—Cu1—Cu1ⁱⁱ	−157.8 (2)
N2—C5—C6—C1	179.2 (3)	C6—N1—Cu1—Cu1ⁱⁱ	12.1 (4)
C4—C5—C6—C1	1.0 (5)	Cu1ⁱ—I1—Cu1—N1	−145.25 (9)
N2—C5—C6—N1	−0.8 (4)	Cu1ⁱⁱ—I1—Cu1—N1	145.04 (9)
C4—C5—C6—N1	−178.9 (3)	Cu1ⁱ—I1—Cu1—I1ⁱⁱⁱ	−27.64 (3)
C7—N1—C6—C1	179.8 (4)	Cu1ⁱⁱ—I1—Cu1—I1ⁱⁱⁱ	−97.34 (2)
Cu1—N1—C6—C1	8.2 (5)	Cu1ⁱ—I1—Cu1—Cu1ⁱⁱⁱ	36.98 (3)
C7—N1—C6—C5	−0.2 (4)	Cu1ⁱⁱ—I1—Cu1—Cu1ⁱⁱⁱ	−32.73 (3)
Cu1—N1—C6—C5	−171.9 (2)	Cu1ⁱⁱ—I1—Cu1—Cu1ⁱ	−69.703 (11)
C6—C5—C4—C3	−0.6 (5)	Cu1ⁱ—I1—Cu1—I1ⁱⁱ	101.19 (3)
N2—C5—C4—C3	−178.2 (3)	Cu1ⁱⁱ—I1—Cu1—I1ⁱⁱ	31.49 (3)
C5—C4—C3—C2	−0.1 (6)	Cu1ⁱ—I1—Cu1—Cu1ⁱⁱ	69.703 (11)

Symmetry codes: (i) y+1/4, −x+7/4, −z+3/4; (ii) −x+2, −y+3/2, z; (iii) −y+7/4, x−1/4, −z+3/4.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10A···O1^iv	0.97	2.60	3.531 (5)	162

Symmetry code: (iv) y−1/4, −x+7/4, z−1/4.

Experimental details

Crystal data
Chemical formula	[Cu₄I₄(C₁₁H₁₂N₂O₂)₄]
M_r	1578.66
Crystal system, space group	Tetragonal, I4₁/a
Temperature (K)	296
a, c (Å)	21.196 (11), 11.581 (7)
V (Å³)	5203 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	4.04
Crystal size (mm)	0.24 × 0.22 × 0.18

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2007)
T_min, T_max	0.768, 0.784
No. of measured, independent and observed [I > 2σ(I)] reflections	13042, 2422, 2018
R_int	0.046
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.023, 0.053, 1.03
No. of reflections	2422
No. of parameters	155
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.35, −0.32

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10A···O1ⁱ	0.97	2.60	3.531 (5)	162

Symmetry code: (i) y−1/4, −x+7/4, z−1/4.

References

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