Bis{N-[5-(4-methoxy­phen­yl)-1,3,4-oxa­diazol-2-yl]ethanimidamidato}copper(II)

Djebli, Y.; Mosbah, S.; Boufas, S.; Bencharif, L.; Roisnel, T.

doi:10.1107/S1600536810009050

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 4| April 2010| Page m410

doi:10.1107/S1600536810009050

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Bis{N-[5-(4-methoxyphenyl)-1,3,4-oxadiazol-2-yl]ethanimidamidato}copper(II)

Yacine Djebli,^a Salima Mosbah,^a Sihem Boufas,^a ^* Leila Bencharif ^a and Thierry Roisnel ^b

^aLaboratoire de Chimie des Materiaux, Université Mentouri, 25000 Constantine, Algeria, and ^bSciences Chimiques de Rennes (UMR CNRS 6226), Université de Rennes 1, Avenue du Général Leclerc, 35042 Rennes Cedex, France
^*Correspondence e-mail: boufas_sihem@yahoo.fr

(Received 16 February 2010; accepted 9 March 2010; online 17 March 2010)

The title compound, [Cu(C₁₁H₁₁N₄O₂)₂], was prepared by solvothermal synthesis using 2-amino-5-(4-methoxyphenyl)-1,3,4-oxadiazole and copper sulfate pentahydrate in an acetonitrile solution. The Cu^II atom lies on an inversion center and is four-coordinated in a slightly distorted square-planar geometry by four N atoms of the ligands obtained from the formation of a bond between the amine N atom of the oxadiazole molecule and the nitrile C atom of the solvent. In the crystal structure an intermolecular N—H⋯N hydrogen bond links inversion-related molecules.

Related literature

For comparative bond lengths in similar coordination compounds, see: Cai, (2009 ). For applications of complexes formed by Schiff base ligands, see: Lu & Schauss (2002 ). For chemotherapeutic effects of 2,5-substituted-1,3,4-oxadiazole derivatives, see: Cao et al. (2002 ); Kadi et al. (2007 ); Zareef et al. (2006 , 2007 , 2008 ).

Experimental

Crystal data

[Cu(C₁₁H₁₁N₄O₂)₂]
M_r = 526.02
Triclinic, $[P \overline 1]$
a = 4.9020 (6) Å
b = 11.2083 (14) Å
c = 11.5739 (14) Å
α = 111.501 (5)°
β = 99.274 (6)°
γ = 91.564 (5)°
V = 581.33 (12) Å³
Z = 1
Mo Kα radiation
μ = 0.99 mm⁻¹
T = 120 K
0.53 × 0.23 × 0.07 mm

Data collection

Bruker APEX diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2002 ) T_min = 0.707, T_max = 0.933
6654 measured reflections
2633 independent reflections
2417 reflections with I > 2σ(I)
R_int = 0.035

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.087
S = 1.06
2633 reflections
166 parameters
H-atom parameters constrained
Δρ_max = 0.42 e Å⁻³
Δρ_min = −0.29 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯N8ⁱ	0.88	2.42	2.983 (2)	123
Symmetry code: (i) -x, -y, -z+1.

Data collection: SMART (Bruker, 2002 ); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810009050/pk2228sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810009050/pk2228Isup2.hkl

checkCIF report

Comment top

In recent years, there has been a considerable effort towards preparation of new materials containing polyfunctional organic ligands able to bind metallic ions by solvothermal synthesis. For example, with Schiff bases ligands, such complexes could be applied in different areas, including biochemistry, electrochemistry, and catalysis (Lu et al., 2002).

The 2,5-substituted-1,3,4-oxadiazole derivatives are of significant interest due to their chemotherapeutic effects (Kadi et al., 2007; Zareef et al., 2008; Zareef et al., 2007; Zareef et al., 2006; Cao et al., 2002). In this paper, we report the structure of one of these compounds with copper (II).

In the centrosymmetric title complex, the Cu (II) atom is located on an inversion center and is four-coordinated in a square planar geometry by four N atoms of the ligands obtained from the formation of a bond between N-amine of the oxadiazole molecule and C-nitrile of the solvent. All the coordinated bond lengths are typical and comparable with those in similar copper (II) complexes (Cai,2009). In the title compound, there is just one weak hydrogen bond N1-H1···N8 linking different inversion (-x, -y, -Z+1) related molecules.

Related literature top

For comparative coordinated bond lengths, see: Cai, (2009). For applications of complexes formed by Schiff base ligands, see: Lu & Schauss (2002). For chemotherapeutic effects of 2,5-substituted-1,3,4-oxadiazole derivatives, see: Cao et al. (2002); Kadi et al. (2007); Zareef et al. (2006, 2007, 2008).

Experimental top

5-(4-Methoxy-phenyl)-2amino-1, 3, 4-oxadiazole (0,2 mmole) and (0,1 mmole) copper sulfate pentahydrate were mixed in 5 ml of acetonitrile. The mixture was placed in a Teflon-lined stainless steel vessel, and heated to 160° C for 16 h. It was then cooled to room temperature over a period of 24 h, and washed using acetonitrile. Brown crystals suitable for X-Ray crystallography were obtained.

Computing details top

Data collection: SAINT (Bruker, 2002); cell refinement: SMART (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

Fig. 1. The molecular structure of the title compound in 30% probability displacement ellipsoids for non-H atoms.

Bis{N-[5-(4-methoxyphenyl)-1,3,4-oxadiazol-2- yl]ethanimidamidato}copper(II) top

Crystal data top

[Cu(C₁₁H₁₁N₄O₂)₂]	Z = 1
M_r = 526.02	F(000) = 271
Triclinic, P1	D_x = 1.503 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 4.9020 (6) Å	Cell parameters from 2925 reflections
b = 11.2083 (14) Å	θ = 3.2–27.4°
c = 11.5739 (14) Å	µ = 0.99 mm⁻¹
α = 111.501 (5)°	T = 120 K
β = 99.274 (6)°	Plate, brown
γ = 91.564 (5)°	0.53 × 0.23 × 0.07 mm
V = 581.33 (12) Å³

Data collection top

Bruker APEXII diffractometer	2633 independent reflections
Radiation source: Enraf-Nonius FR590	2417 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.035
CCD rotation images, thin slices scans	θ_max = 27.5°, θ_min = 3.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 2002)	h = −6→6
T_min = 0.707, T_max = 0.933	k = −14→14
6654 measured reflections	l = −15→15

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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.087	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.0355P)² + 0.2373P] where P = (F_o² + 2F_c²)/3
2633 reflections	(Δ/σ)_max < 0.001
166 parameters	Δρ_max = 0.42 e Å⁻³
0 restraints	Δρ_min = −0.29 e Å⁻³

Crystal data top

[Cu(C₁₁H₁₁N₄O₂)₂]	γ = 91.564 (5)°
M_r = 526.02	V = 581.33 (12) Å³
Triclinic, P1	Z = 1
a = 4.9020 (6) Å	Mo Kα radiation
b = 11.2083 (14) Å	µ = 0.99 mm⁻¹
c = 11.5739 (14) Å	T = 120 K
α = 111.501 (5)°	0.53 × 0.23 × 0.07 mm
β = 99.274 (6)°

Data collection top

Bruker APEXII diffractometer	2633 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2002)	2417 reflections with I > 2σ(I)
T_min = 0.707, T_max = 0.933	R_int = 0.035
6654 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.087	H-atom parameters constrained
S = 1.06	Δρ_max = 0.42 e Å⁻³
2633 reflections	Δρ_min = −0.29 e Å⁻³
166 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cu1	0	0	0.5	0.02231 (12)
N1	0.1428 (3)	−0.09664 (16)	0.34848 (16)	0.0245 (4)
H1	0.0696	−0.1769	0.3098	0.029*
C2	0.3294 (4)	−0.06281 (19)	0.29405 (19)	0.0240 (4)
C3	0.3968 (5)	−0.1574 (2)	0.1722 (2)	0.0314 (5)
H3A	0.3138	−0.2438	0.1562	0.047*
H3B	0.5986	−0.1581	0.1794	0.047*
H3C	0.3216	−0.1314	0.1021	0.047*
N4	0.4749 (3)	0.05335 (16)	0.33696 (16)	0.0255 (4)
C5	0.4203 (4)	0.14395 (19)	0.44061 (19)	0.0229 (4)
N6	0.2379 (3)	0.14792 (15)	0.51450 (16)	0.0230 (4)
O7	0.5775 (3)	0.26005 (13)	0.48592 (13)	0.0244 (3)
N8	0.2771 (3)	0.26958 (16)	0.61315 (17)	0.0257 (4)
C9	0.4788 (4)	0.33114 (19)	0.59302 (19)	0.0234 (4)
C10	0.6076 (4)	0.46056 (19)	0.6693 (2)	0.0251 (4)
C11	0.5447 (5)	0.5265 (2)	0.7888 (2)	0.0368 (5)
H11	0.417	0.4865	0.8202	0.044*
C12	0.6665 (5)	0.6494 (2)	0.8615 (2)	0.0385 (6)
H12	0.6239	0.6931	0.9429	0.046*
C13	0.8519 (4)	0.70962 (19)	0.8158 (2)	0.0266 (4)
C14	0.9179 (5)	0.6449 (2)	0.6975 (2)	0.0309 (5)
H14	1.0455	0.6849	0.6661	0.037*
C15	0.7950 (5)	0.5211 (2)	0.6259 (2)	0.0321 (5)
H15	0.8404	0.4767	0.5452	0.038*
O16	0.9576 (3)	0.83100 (14)	0.89471 (14)	0.0336 (4)
C17	1.1494 (5)	0.8972 (2)	0.8518 (2)	0.0321 (5)
H17A	1.3138	0.8496	0.8384	0.048*
H17B	1.205	0.9841	0.9154	0.048*
H17C	1.0601	0.903	0.7722	0.048*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu1	0.02216 (19)	0.01886 (19)	0.0244 (2)	−0.00107 (13)	0.00942 (14)	0.00450 (14)
N1	0.0251 (8)	0.0203 (8)	0.0251 (9)	−0.0016 (6)	0.0080 (7)	0.0039 (7)
C2	0.0251 (10)	0.0244 (10)	0.0225 (10)	0.0037 (8)	0.0058 (8)	0.0083 (8)
C3	0.0365 (12)	0.0275 (11)	0.0263 (11)	−0.0012 (9)	0.0110 (9)	0.0039 (9)
N4	0.0290 (9)	0.0231 (9)	0.0238 (9)	−0.0008 (7)	0.0106 (7)	0.0057 (7)
C5	0.0225 (9)	0.0206 (10)	0.0261 (10)	−0.0003 (7)	0.0048 (8)	0.0094 (8)
N6	0.0233 (8)	0.0199 (8)	0.0238 (8)	0.0002 (6)	0.0094 (7)	0.0040 (7)
O7	0.0277 (7)	0.0197 (7)	0.0247 (7)	−0.0024 (5)	0.0093 (6)	0.0056 (6)
N8	0.0266 (9)	0.0187 (8)	0.0279 (9)	−0.0001 (7)	0.0097 (7)	0.0027 (7)
C9	0.0247 (10)	0.0208 (10)	0.0243 (10)	0.0022 (8)	0.0081 (8)	0.0064 (8)
C10	0.0257 (10)	0.0203 (10)	0.0274 (11)	0.0015 (8)	0.0068 (8)	0.0060 (8)
C11	0.0446 (13)	0.0299 (12)	0.0344 (12)	−0.0070 (10)	0.0200 (11)	0.0061 (10)
C12	0.0540 (15)	0.0298 (12)	0.0281 (12)	−0.0058 (10)	0.0201 (11)	0.0021 (10)
C13	0.0294 (10)	0.0205 (10)	0.0265 (10)	−0.0013 (8)	0.0053 (9)	0.0053 (8)
C14	0.0354 (12)	0.0251 (11)	0.0305 (11)	−0.0060 (9)	0.0127 (9)	0.0061 (9)
C15	0.0397 (12)	0.0252 (11)	0.0257 (11)	−0.0046 (9)	0.0157 (9)	−0.0004 (9)
O16	0.0432 (9)	0.0231 (8)	0.0287 (8)	−0.0081 (6)	0.0108 (7)	0.0021 (6)
C17	0.0365 (12)	0.0225 (11)	0.0343 (12)	−0.0059 (9)	0.0070 (10)	0.0075 (9)

Geometric parameters (Å, º) top

Cu1—N6ⁱ	1.9403 (16)	C9—C10	1.454 (3)
Cu1—N6	1.9403 (16)	C10—C15	1.386 (3)
Cu1—N1ⁱ	1.9451 (17)	C10—C11	1.398 (3)
Cu1—N1	1.9451 (17)	C11—C12	1.380 (3)
N1—C2	1.311 (3)	C11—H11	0.95
N1—H1	0.88	C12—C13	1.394 (3)
C2—N4	1.346 (3)	C12—H12	0.95
C2—C3	1.515 (3)	C13—O16	1.361 (2)
C3—H3A	0.98	C13—C14	1.390 (3)
C3—H3B	0.98	C14—C15	1.388 (3)
C3—H3C	0.98	C14—H14	0.95
N4—C5	1.329 (3)	C15—H15	0.95
C5—N6	1.324 (3)	O16—C17	1.436 (3)
C5—O7	1.370 (2)	C17—H17A	0.98
N6—N8	1.405 (2)	C17—H17B	0.98
O7—C9	1.377 (2)	C17—H17C	0.98
N8—C9	1.289 (2)

N6ⁱ—Cu1—N6	180.00 (6)	N8—C9—C10	127.92 (19)
N6ⁱ—Cu1—N1ⁱ	87.39 (7)	O7—C9—C10	119.18 (17)
N6—Cu1—N1ⁱ	92.61 (7)	C15—C10—C11	118.54 (19)
N6ⁱ—Cu1—N1	92.61 (7)	C15—C10—C9	121.09 (19)
N6—Cu1—N1	87.39 (7)	C11—C10—C9	120.36 (19)
N1ⁱ—Cu1—N1	180	C12—C11—C10	120.5 (2)
C2—N1—Cu1	131.13 (14)	C12—C11—H11	119.7
C2—N1—H1	114.4	C10—C11—H11	119.7
Cu1—N1—H1	114.4	C11—C12—C13	120.2 (2)
N1—C2—N4	125.48 (18)	C11—C12—H12	119.9
N1—C2—C3	120.38 (18)	C13—C12—H12	119.9
N4—C2—C3	114.13 (17)	O16—C13—C14	124.78 (19)
C2—C3—H3A	109.5	O16—C13—C12	115.32 (19)
C2—C3—H3B	109.5	C14—C13—C12	119.90 (19)
H3A—C3—H3B	109.5	C15—C14—C13	119.2 (2)
C2—C3—H3C	109.5	C15—C14—H14	120.4
H3A—C3—H3C	109.5	C13—C14—H14	120.4
H3B—C3—H3C	109.5	C10—C15—C14	121.6 (2)
C5—N4—C2	118.09 (17)	C10—C15—H15	119.2
N6—C5—N4	133.31 (18)	C14—C15—H15	119.2
N6—C5—O7	109.26 (17)	C13—O16—C17	117.41 (17)
N4—C5—O7	117.43 (17)	O16—C17—H17A	109.5
C5—N6—N8	108.50 (16)	O16—C17—H17B	109.5
C5—N6—Cu1	124.23 (14)	H17A—C17—H17B	109.5
N8—N6—Cu1	126.65 (13)	O16—C17—H17C	109.5
C5—O7—C9	104.03 (14)	H17A—C17—H17C	109.5
C9—N8—N6	105.28 (16)	H17B—C17—H17C	109.5
N8—C9—O7	112.90 (17)

N6ⁱ—Cu1—N1—C2	−177.96 (19)	N6—N8—C9—O7	0.9 (2)
N6—Cu1—N1—C2	2.04 (19)	N6—N8—C9—C10	−178.20 (19)
Cu1—N1—C2—N4	1.8 (3)	C5—O7—C9—N8	−1.4 (2)
Cu1—N1—C2—C3	−178.05 (14)	C5—O7—C9—C10	177.76 (17)
N1—C2—N4—C5	−2.6 (3)	N8—C9—C10—C15	−170.3 (2)
C3—C2—N4—C5	177.23 (17)	O7—C9—C10—C15	10.7 (3)
C2—N4—C5—N6	−2.5 (3)	N8—C9—C10—C11	9.8 (3)
C2—N4—C5—O7	177.53 (17)	O7—C9—C10—C11	−169.16 (19)
N4—C5—N6—N8	179.1 (2)	C15—C10—C11—C12	0.2 (4)
O7—C5—N6—N8	−0.9 (2)	C9—C10—C11—C12	180.0 (2)
N4—C5—N6—Cu1	7.6 (3)	C10—C11—C12—C13	0.7 (4)
O7—C5—N6—Cu1	−172.39 (12)	C11—C12—C13—O16	179.4 (2)
N1ⁱ—Cu1—N6—C5	174.14 (16)	C11—C12—C13—C14	−1.1 (4)
N1—Cu1—N6—C5	−5.86 (16)	O16—C13—C14—C15	−179.9 (2)
N1ⁱ—Cu1—N6—N8	4.22 (16)	C12—C13—C14—C15	0.6 (3)
N1—Cu1—N6—N8	−175.78 (16)	C11—C10—C15—C14	−0.6 (3)
N6—C5—O7—C9	1.4 (2)	C9—C10—C15—C14	179.6 (2)
N4—C5—O7—C9	−178.66 (17)	C13—C14—C15—C10	0.2 (4)
C5—N6—N8—C9	0.0 (2)	C14—C13—O16—C17	0.6 (3)
Cu1—N6—N8—C9	171.26 (14)	C12—C13—O16—C17	−179.9 (2)

Symmetry code: (i) −x, −y, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N8ⁱ	0.88	2.42	2.983 (2)	123

Symmetry code: (i) −x, −y, −z+1.

Experimental details

Crystal data
Chemical formula	[Cu(C₁₁H₁₁N₄O₂)₂]
M_r	526.02
Crystal system, space group	Triclinic, P1
Temperature (K)	120
a, b, c (Å)	4.9020 (6), 11.2083 (14), 11.5739 (14)
α, β, γ (°)	111.501 (5), 99.274 (6), 91.564 (5)
V (Å³)	581.33 (12)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	0.99
Crystal size (mm)	0.53 × 0.23 × 0.07

Data collection
Diffractometer	Bruker APEXII diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2002)
T_min, T_max	0.707, 0.933
No. of measured, independent and observed [I > 2σ(I)] reflections	6654, 2633, 2417
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.087, 1.06
No. of reflections	2633
No. of parameters	166
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.42, −0.29

Computer programs: SAINT (Bruker, 2002), SMART (Bruker, 2002), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N8ⁱ	0.8800	2.4200	2.983 (2)	123.00

Symmetry code: (i) −x, −y, −z+1.

Acknowledgements

This work was supported by the Laboratoire de Chimie des Materiaux, Faculté des Sciences, Université Mentouri. We would like to thank J.-Y. Saillard of Rennes 1 University for providing diffraction facilities.

References

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ISSN: 2056-9890

Volume 66| Part 4| April 2010| Page m410

doi:10.1107/S1600536810009050

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