Di-μ-chlorido-bis­(chlorido{2-[(4-ethyl­phen­yl)imino­meth­yl]pyridine-κ2N,N′}copper(II))

Dehghanpour, S.; Mahmoudi, A.; Khalaj, M.; Abbasi, S.; Mojahed, F.

doi:10.1107/S1600536811032053

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 9| September 2011| Page m1296

doi:10.1107/S1600536811032053

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Di-μ-chlorido-bis(chlorido{2-[(4-ethylphenyl)iminomethyl]pyridine-κ²N,N′}copper(II))

Saeed Dehghanpour,^a ^* Ali Mahmoudi,^b Mehdi Khalaj,^c Somayeh Abbasi ^b and Fresia Mojahed ^d

^aDepartment of Chemistry, Alzahra University, Tehran, Iran, ^bDepartment of Chemistry, Islamic Azad University, Karaj Branch, Karaj, Iran, ^cDepartment of Chemistry, Islamic Azad University, Buinzahra Branch, Qazvin, Iran, and ^dDepartment of Chemistry, Faculty of Science, Urmia University, Urmia, 57159-165, Iran
^*Correspondence e-mail: dehganpour_farasha@yahoo.com

(Received 19 July 2011; accepted 8 August 2011; online 27 August 2011)

The binuclear title complex, [Cu₂Cl₄(C₁₄H₁₄N₂)₂], is located on a crystallographic inversion centre. The Cu^II ion is in a distorted square-pyramid coordination environment formed by the bichelating N-heterocyclic ligand, two bridging Cl atoms and one terminal Cl atom. One of the bridging Cu—Cl bonds is significantly longer than the other.

Related literature

For the synthesis of the ligand, see: Dehghanpour et al. (2009 ). For background to diimine complexes and related structures, see: Mahmoudi et al. (2009 ); Salehzadeh et al. (2011 ).

Experimental

Crystal data

[Cu₂Cl₄(C₁₄H₁₄N₂)₂]
M_r = 689.42
Monoclinic, P 2₁ /c
a = 10.1254 (3) Å
b = 8.8384 (3) Å
c = 16.2117 (4) Å
β = 100.8830 (18)°
V = 1424.73 (7) Å³
Z = 2
Mo Kα radiation
μ = 1.89 mm⁻¹
T = 150 K
0.18 × 0.18 × 0.12 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SORTAV; Blessing, 1995 ) T_min = 0.672, T_max = 0.795
13286 measured reflections
3246 independent reflections
2568 reflections with I > 2σ(I)
R_int = 0.043

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.090
S = 1.11
3246 reflections
173 parameters
H-atom parameters constrained
Δρ_max = 0.60 e Å⁻³
Δρ_min = −0.59 e Å⁻³

Table 1
Selected bond lengths (Å)

Cu1—N1	2.040 (2)
Cu1—N2	2.046 (2)
Cu1—Cl2	2.2423 (7)
Cu1—Cl1	2.3067 (7)
Cu1—Cl1ⁱ	2.5883 (7)
Symmetry code: (i) -x+1, -y+1, -z+1.

Data collection: COLLECT (Nonius, 2002 ); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997 ); data reduction: DENZO-SMN; program(s) used to solve structure: SIR92 (Altomare et al., 1994 ); program(s) used to refine structure: SHELXTL (Sheldrick, 2008 ); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811032053/kj2183sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811032053/kj2183Isup2.hkl

checkCIF report

Comment top

In our ongoing studies on the synthesis, structural and spectroscopic characterization of transition metal complexes with diimine ligands (Dehghanpour et al., 2009; Salehzadeh et al., 2011), here we report the crystal structure of the title complex. The title complex was prepared by the reaction of CuCl₂ with the bidentate ligand (4-methylphenyl)pyridin-2-ylmethyleneamine (Mahmoudi et al., 2009).

The molecluar structure of the title complex is shown in Fig. 1. The Cu^II ion is in a distorted squar pyramid environment formed by a bis-chelating ligand, two bridging Cl atoms and one terminal Cl atom. A comparison of the dihedral angles between the planes of the pyridine, chelate and the benzene ring indicate that the ligand is distorted from planarity, with twist of 41.9 (2)° between the chelate (N1C5C6N2) and the benzene (C7C8C9C10C11C12) planes.One of the bridging Cu—Cl bonds is significantly longer than the other.

Related literature top

For the synthesis of the ligand, see: Dehghanpour et al. (2009). For background to diimine complexes and related structures see: Mahmoudi et al. (2009); Salehzadeh et al. (2011).

Experimental top

The title complex was prepared by the reaction of CuCl₂ (13.4 mg, 0.1 mmole) and (4-methylphenyl)pyridin-2-ylmethyleneamine (21.0 mg, 0.1) in 15 ml methanol at room temperature. The solution was allowed to stand at room temperature and green crystals of the title compound suitable for X-ray analysis precipitated within few days.

Computing details top

Data collection: COLLECT (Nonius, 2002); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. A view of the structure of the title complex, with displacement ellipsoids drawn at 50% probability level.

Di-µ-chlorido-bis(chlorido{2-[(4-ethylphenyl)iminomethyl]pyridine- κ²N,N'}copper(II)) top

Crystal data top

[Cu₂Cl₄(C₁₄H₁₄N₂)₂]	F(000) = 700
M_r = 689.42	D_x = 1.607 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5841 reflections
a = 10.1254 (3) Å	θ = 2.6–27.5°
b = 8.8384 (3) Å	µ = 1.89 mm⁻¹
c = 16.2117 (4) Å	T = 150 K
β = 100.8830 (18)°	Block, green
V = 1424.73 (7) Å³	0.18 × 0.18 × 0.12 mm
Z = 2

Data collection top

Nonius KappaCCD diffractometer	3246 independent reflections
Radiation source: fine-focus sealed tube	2568 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.043
Detector resolution: 9 pixels mm^-1	θ_max = 27.5°, θ_min = 2.6°
ϕ scans and ω scans with κ offsets	h = −13→10
Absorption correction: multi-scan (SORTAV (Blessing, 1995)	k = −11→11
T_min = 0.672, T_max = 0.795	l = −20→21
13286 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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.090	H-atom parameters constrained
S = 1.11	w = 1/[σ²(F_o²) + (0.0322P)² + 1.7627P] where P = (F_o² + 2F_c²)/3
3246 reflections	(Δ/σ)_max = 0.001
173 parameters	Δρ_max = 0.60 e Å⁻³
0 restraints	Δρ_min = −0.59 e Å⁻³

Crystal data top

[Cu₂Cl₄(C₁₄H₁₄N₂)₂]	V = 1424.73 (7) Å³
M_r = 689.42	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 10.1254 (3) Å	µ = 1.89 mm⁻¹
b = 8.8384 (3) Å	T = 150 K
c = 16.2117 (4) Å	0.18 × 0.18 × 0.12 mm
β = 100.8830 (18)°

Data collection top

Nonius KappaCCD diffractometer	3246 independent reflections
Absorption correction: multi-scan (SORTAV (Blessing, 1995)	2568 reflections with I > 2σ(I)
T_min = 0.672, T_max = 0.795	R_int = 0.043
13286 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.090	H-atom parameters constrained
S = 1.11	Δρ_max = 0.60 e Å⁻³
3246 reflections	Δρ_min = −0.59 e Å⁻³
173 parameters

Special details top

Experimental. multi-scan from symmetry-related measurements SORTAV (Blessing, 1995)

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
Cu1	0.49287 (3)	0.40798 (4)	0.59239 (2)	0.01724 (11)
Cl1	0.65548 (6)	0.56294 (8)	0.55534 (4)	0.01911 (16)
Cl2	0.41609 (7)	0.59028 (8)	0.66720 (4)	0.02404 (17)
N1	0.5981 (2)	0.2194 (3)	0.57146 (14)	0.0185 (5)
N2	0.3756 (2)	0.2450 (3)	0.63198 (13)	0.0178 (5)
C1	0.7060 (3)	0.2085 (3)	0.53486 (17)	0.0222 (6)
H1A	0.7364	0.2955	0.5095	0.027*
C2	0.7742 (3)	0.0725 (3)	0.53322 (18)	0.0240 (6)
H2A	0.8512	0.0678	0.5076	0.029*
C3	0.7307 (3)	−0.0556 (3)	0.56855 (18)	0.0243 (6)
H3A	0.7777	−0.1486	0.5685	0.029*
C4	0.6167 (3)	−0.0455 (3)	0.60428 (18)	0.0224 (6)
H4A	0.5825	−0.1322	0.6279	0.027*
C5	0.5544 (3)	0.0924 (3)	0.60479 (16)	0.0173 (6)
C6	0.4297 (3)	0.1137 (3)	0.63732 (17)	0.0197 (6)
H6A	0.3902	0.0318	0.6618	0.024*
C7	0.2512 (3)	0.2625 (3)	0.66176 (17)	0.0193 (6)
C8	0.2360 (3)	0.1939 (3)	0.73601 (17)	0.0226 (6)
H8A	0.3085	0.1399	0.7688	0.027*
C9	0.1134 (3)	0.2047 (3)	0.76209 (17)	0.0225 (6)
H9A	0.1029	0.1566	0.8129	0.027*
C10	0.0059 (3)	0.2836 (3)	0.71632 (18)	0.0228 (6)
C11	0.0253 (3)	0.3551 (4)	0.64241 (18)	0.0250 (6)
H11A	−0.0465	0.4107	0.6100	0.030*
C12	0.1477 (3)	0.3464 (3)	0.61556 (17)	0.0233 (6)
H12A	0.1600	0.3974	0.5660	0.028*
C13	−0.1281 (3)	0.2884 (4)	0.74484 (18)	0.0270 (7)
H13A	−0.1718	0.1881	0.7348	0.032*
H13B	−0.1868	0.3633	0.7103	0.032*
C14	−0.1168 (3)	0.3292 (4)	0.83719 (19)	0.0332 (7)
H14A	−0.2069	0.3336	0.8510	0.050*
H14B	−0.0731	0.4280	0.8479	0.050*
H14C	−0.0633	0.2523	0.8721	0.050*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu1	0.01785 (18)	0.0172 (2)	0.01712 (18)	−0.00025 (13)	0.00446 (13)	0.00089 (13)
Cl1	0.0199 (3)	0.0202 (4)	0.0171 (3)	−0.0028 (3)	0.0029 (2)	0.0011 (3)
Cl2	0.0224 (3)	0.0254 (4)	0.0252 (4)	0.0003 (3)	0.0070 (3)	−0.0061 (3)
N1	0.0169 (11)	0.0186 (12)	0.0195 (12)	0.0009 (9)	0.0022 (9)	0.0004 (9)
N2	0.0186 (11)	0.0191 (12)	0.0158 (11)	−0.0023 (9)	0.0037 (9)	−0.0004 (9)
C1	0.0219 (14)	0.0231 (16)	0.0222 (14)	−0.0025 (12)	0.0053 (11)	0.0021 (12)
C2	0.0212 (14)	0.0249 (16)	0.0269 (16)	0.0016 (12)	0.0065 (12)	−0.0005 (12)
C3	0.0254 (15)	0.0213 (16)	0.0259 (16)	0.0030 (12)	0.0044 (12)	−0.0015 (12)
C4	0.0245 (15)	0.0173 (14)	0.0245 (15)	0.0002 (12)	0.0021 (12)	0.0013 (12)
C5	0.0182 (13)	0.0201 (15)	0.0128 (13)	−0.0013 (11)	0.0008 (10)	0.0013 (11)
C6	0.0222 (14)	0.0201 (15)	0.0168 (14)	−0.0042 (11)	0.0036 (11)	0.0022 (11)
C7	0.0182 (13)	0.0203 (15)	0.0194 (14)	−0.0024 (11)	0.0038 (11)	−0.0011 (11)
C8	0.0225 (14)	0.0237 (15)	0.0211 (14)	0.0015 (12)	0.0032 (11)	0.0017 (12)
C9	0.0238 (14)	0.0254 (16)	0.0190 (14)	−0.0008 (12)	0.0057 (11)	0.0012 (12)
C10	0.0207 (14)	0.0230 (16)	0.0253 (15)	−0.0046 (12)	0.0062 (12)	−0.0042 (12)
C11	0.0192 (14)	0.0306 (17)	0.0246 (15)	0.0020 (12)	0.0024 (11)	0.0027 (13)
C12	0.0252 (15)	0.0265 (16)	0.0181 (14)	0.0014 (12)	0.0037 (11)	0.0045 (12)
C13	0.0208 (14)	0.0346 (18)	0.0262 (15)	−0.0013 (13)	0.0061 (12)	0.0001 (13)
C14	0.0292 (16)	0.043 (2)	0.0295 (17)	0.0026 (15)	0.0116 (14)	−0.0006 (15)

Geometric parameters (Å, º) top

Cu1—N1	2.040 (2)	C6—H6A	0.9500
Cu1—N2	2.046 (2)	C7—C8	1.382 (4)
Cu1—Cl2	2.2423 (7)	C7—C12	1.383 (4)
Cu1—Cl1	2.3067 (7)	C8—C9	1.388 (4)
Cu1—Cl1ⁱ	2.5883 (7)	C8—H8A	0.9500
Cl1—Cu1ⁱ	2.5883 (7)	C9—C10	1.384 (4)
N1—C1	1.342 (3)	C9—H9A	0.9500
N1—C5	1.356 (3)	C10—C11	1.401 (4)
N2—C6	1.280 (3)	C10—C13	1.514 (4)
N2—C7	1.439 (3)	C11—C12	1.390 (4)
C1—C2	1.388 (4)	C11—H11A	0.9500
C1—H1A	0.9500	C12—H12A	0.9500
C2—C3	1.378 (4)	C13—C14	1.523 (4)
C2—H2A	0.9500	C13—H13A	0.9900
C3—C4	1.389 (4)	C13—H13B	0.9900
C3—H3A	0.9500	C14—H14A	0.9800
C4—C5	1.373 (4)	C14—H14B	0.9800
C4—H4A	0.9500	C14—H14C	0.9800
C5—C6	1.469 (4)

N1—Cu1—N2	80.19 (9)	N2—C6—H6A	120.7
N1—Cu1—Cl2	157.23 (7)	C5—C6—H6A	120.7
N2—Cu1—Cl2	93.15 (7)	C8—C7—C12	120.6 (2)
N1—Cu1—Cl1	91.19 (6)	C8—C7—N2	119.6 (2)
N2—Cu1—Cl1	170.06 (7)	C12—C7—N2	119.8 (2)
Cl2—Cu1—Cl1	92.96 (3)	C7—C8—C9	119.2 (3)
N1—Cu1—Cl1ⁱ	99.05 (6)	C7—C8—H8A	120.4
N2—Cu1—Cl1ⁱ	95.18 (6)	C9—C8—H8A	120.4
Cl2—Cu1—Cl1ⁱ	103.25 (3)	C10—C9—C8	122.0 (3)
Cl1—Cu1—Cl1ⁱ	91.04 (2)	C10—C9—H9A	119.0
Cu1—Cl1—Cu1ⁱ	88.96 (2)	C8—C9—H9A	119.0
C1—N1—C5	118.1 (2)	C9—C10—C11	117.5 (3)
C1—N1—Cu1	128.83 (19)	C9—C10—C13	120.6 (3)
C5—N1—Cu1	112.96 (17)	C11—C10—C13	121.8 (3)
C6—N2—C7	117.7 (2)	C12—C11—C10	121.3 (3)
C6—N2—Cu1	113.14 (18)	C12—C11—H11A	119.3
C7—N2—Cu1	128.77 (18)	C10—C11—H11A	119.3
N1—C1—C2	121.4 (3)	C7—C12—C11	119.3 (3)
N1—C1—H1A	119.3	C7—C12—H12A	120.3
C2—C1—H1A	119.3	C11—C12—H12A	120.3
C3—C2—C1	120.2 (3)	C10—C13—C14	113.7 (2)
C3—C2—H2A	119.9	C10—C13—H13A	108.8
C1—C2—H2A	119.9	C14—C13—H13A	108.8
C2—C3—C4	118.5 (3)	C10—C13—H13B	108.8
C2—C3—H3A	120.8	C14—C13—H13B	108.8
C4—C3—H3A	120.8	H13A—C13—H13B	107.7
C5—C4—C3	118.6 (3)	C13—C14—H14A	109.5
C5—C4—H4A	120.7	C13—C14—H14B	109.5
C3—C4—H4A	120.7	H14A—C14—H14B	109.5
N1—C5—C4	123.2 (2)	C13—C14—H14C	109.5
N1—C5—C6	113.8 (2)	H14A—C14—H14C	109.5
C4—C5—C6	122.9 (2)	H14B—C14—H14C	109.5
N2—C6—C5	118.6 (2)

N1—Cu1—Cl1—Cu1ⁱ	99.07 (6)	Cu1—N1—C5—C6	8.5 (3)
Cl2—Cu1—Cl1—Cu1ⁱ	−103.33 (3)	C3—C4—C5—N1	0.5 (4)
Cl1ⁱ—Cu1—Cl1—Cu1ⁱ	0.0	C3—C4—C5—C6	177.0 (3)
N2—Cu1—N1—C1	174.6 (2)	C7—N2—C6—C5	178.1 (2)
Cl2—Cu1—N1—C1	−110.9 (2)	Cu1—N2—C6—C5	−8.1 (3)
Cl1—Cu1—N1—C1	−10.3 (2)	N1—C5—C6—N2	−0.3 (4)
Cl1ⁱ—Cu1—N1—C1	80.9 (2)	C4—C5—C6—N2	−177.0 (3)
N2—Cu1—N1—C5	−9.83 (18)	C6—N2—C7—C8	42.2 (4)
Cl2—Cu1—N1—C5	64.6 (3)	Cu1—N2—C7—C8	−130.5 (2)
Cl1—Cu1—N1—C5	165.18 (17)	C6—N2—C7—C12	−137.1 (3)
Cl1ⁱ—Cu1—N1—C5	−103.57 (17)	Cu1—N2—C7—C12	50.2 (3)
N1—Cu1—N2—C6	9.73 (19)	C12—C7—C8—C9	2.6 (4)
Cl2—Cu1—N2—C6	−148.34 (18)	N2—C7—C8—C9	−176.7 (2)
N1—Cu1—N2—C7	−177.3 (2)	C7—C8—C9—C10	−0.6 (4)
Cl2—Cu1—N2—C7	24.6 (2)	C8—C9—C10—C11	−0.9 (4)
C5—N1—C1—C2	−2.0 (4)	C8—C9—C10—C13	177.7 (3)
Cu1—N1—C1—C2	173.3 (2)	C9—C10—C11—C12	0.5 (4)
N1—C1—C2—C3	0.9 (4)	C13—C10—C11—C12	−178.1 (3)
C1—C2—C3—C4	1.0 (4)	C8—C7—C12—C11	−3.0 (4)
C2—C3—C4—C5	−1.7 (4)	N2—C7—C12—C11	176.3 (3)
C1—N1—C5—C4	1.3 (4)	C10—C11—C12—C7	1.5 (4)
Cu1—N1—C5—C4	−174.7 (2)	C9—C10—C13—C14	49.0 (4)
C1—N1—C5—C6	−175.4 (2)	C11—C10—C13—C14	−132.5 (3)

Symmetry code: (i) −x+1, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	[Cu₂Cl₄(C₁₄H₁₄N₂)₂]
M_r	689.42
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	150
a, b, c (Å)	10.1254 (3), 8.8384 (3), 16.2117 (4)
β (°)	100.8830 (18)
V (Å³)	1424.73 (7)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.89
Crystal size (mm)	0.18 × 0.18 × 0.12

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	Multi-scan (SORTAV (Blessing, 1995)
T_min, T_max	0.672, 0.795
No. of measured, independent and observed [I > 2σ(I)] reflections	13286, 3246, 2568
R_int	0.043
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.090, 1.11
No. of reflections	3246
No. of parameters	173
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.60, −0.59

Computer programs: COLLECT (Nonius, 2002), DENZO-SMN (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), SHELXTL (Sheldrick, 2008), PLATON (Spek, 2009).

Selected bond lengths (Å) top

Cu1—N1	2.040 (2)	Cu1—Cl1	2.3067 (7)
Cu1—N2	2.046 (2)	Cu1—Cl1ⁱ	2.5883 (7)
Cu1—Cl2	2.2423 (7)

Symmetry code: (i) −x+1, −y+1, −z+1.

Acknowledgements

The authors would like to acknowledge the Alzahra and Islamic Azad University Research Councils for partial support of this work.

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