A second monoclinic polymorph of di-μ-chlorido-bis-(chlorido{2-[(4-ethyl-phen-yl)imino-meth-yl]pyridine-κ²N,N'}copper(II)).

The title compound, [Cu₂Cl₄(C₁₄H₁₄N₂)₂], is a new polymorph of a previously reported compound [Dehghanpour et al. (2011 ▶). Acta Cryst. E67, m1296]. The current polymorph was obtained from an acetonitrile solution of the title compound. Like the first polymorph, it is monoclinic (space group P2₁/c). The unique Cu(II) ion in the title centrosymmetric dinuclear complex is in a distorted trigonal-bipyramidal coordination environment formed by the bis--chelating N-heterocyclic ligand, two bridging Cl ligands and one terminal Cl ligand. In the crystal, weak C-H⋯Cl hydrogen bonds are observed in addition to π-π stacking inter-actions, with a centroid-centroid distance of 3.6597 (18) Å.

Related literature

For the synthesis of the ligand, see: Dehghanpour et al. (2009 ▶). For background to diimine complexes and related structures, see: Dehghanpour et al. (2011 ▶); Salehzadeh et al. (2011 ▶). For an index of trigonality as a general descriptor of five-coord­inate complexes, see: Addison et al. (1984 ▶).

Experimental

Crystal data

[Cu2Cl4(C14H14N2)2]

M = 689.42

Monoclinic,

a = 7.8480 (4) Å

b = 13.7160 (6) Å

c = 14.4601 (7) Å

β = 113.924 (3)°

V = 1422.80 (12) Å3

Z = 2

Mo Kα radiation

μ = 1.90 mm−1

T = 150 K

0.30 × 0.25 × 0.20 mm

Data collection

Nonius KappaCCD diffractometer

Absorption correction: multi-scan (SORTAV; Blessing, 1995 ▶) T min = 0.581, T max = 0.689

7862 measured reflections

3249 independent reflections

2399 reflections with I > 2σ(I)

R int = 0.045

Refinement

R[F 2 > 2σ(F 2)] = 0.040

wR(F 2) = 0.102

S = 1.05

3249 reflections

173 parameters

H-atom parameters constrained

Δρmax = 0.76 e Å−3

Δρmin = −0.70 e Å−3

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 ▶) and Mercury (Macrae et al., 2006) ▶; software used to prepare material for publication: SHELXTL.

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812026347/fb2253sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812026347/fb2253Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

[Cu2Cl4(C14H14N2)2]	F(000) = 700
Mr = 689.42	Dx = 1.609 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 4440 reflections
a = 7.8480 (4) Å	θ = 2.6–27.5°
b = 13.7160 (6) Å	µ = 1.90 mm−1
c = 14.4601 (7) Å	T = 150 K
β = 113.924 (3)°	Block, orange
V = 1422.80 (12) Å3	0.30 × 0.25 × 0.20 mm
Z = 2

Nonius KappaCCD diffractometer	3249 independent reflections
Radiation source: fine-focus sealed tube	2399 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.045
Detector resolution: 9 pixels mm-1	θmax = 27.5°, θmin = 2.8°
φ scans and ω scans with κ offsets	h = −10→10
Absorption correction: multi-scan (SORTAV; Blessing, 1995)	k = −17→15
Tmin = 0.581, Tmax = 0.689	l = −12→18
7862 measured reflections

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)] = 0.040	Hydrogen site location: difference Fourier map
wR(F2) = 0.102	H-atom parameters constrained
S = 1.05	w = 1/[σ2(Fo2) + (0.0441P)2 + 0.8729P] where P = (Fo2 + 2Fc2)/3
3249 reflections	(Δ/σ)max = 0.001
173 parameters	Δρmax = 0.76 e Å−3
0 restraints	Δρmin = −0.70 e Å−3
55 constraints

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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.

	x	y	z	Uiso*/Ueq
Cu1	0.50129 (5)	0.45502 (2)	0.61249 (3)	0.02458 (13)
Cl1	0.60970 (11)	0.59376 (5)	0.56397 (5)	0.0301 (2)
Cl2	0.33826 (11)	0.53968 (5)	0.68632 (6)	0.03089 (19)
N1	0.7670 (3)	0.40393 (17)	0.70183 (18)	0.0239 (5)
N2	0.4320 (3)	0.32164 (16)	0.64881 (17)	0.0227 (5)
C1	0.9333 (4)	0.4446 (2)	0.7264 (2)	0.0290 (7)
H1A	0.9403	0.5066	0.6987	0.035*
C2	1.0974 (4)	0.4000 (2)	0.7912 (2)	0.0329 (7)
H2A	1.2139	0.4315	0.8077	0.040*
C3	1.0897 (4)	0.3100 (2)	0.8311 (2)	0.0337 (7)
H3A	1.2003	0.2784	0.8757	0.040*
C4	0.9176 (4)	0.2662 (2)	0.8049 (2)	0.0342 (7)
H4A	0.9079	0.2034	0.8301	0.041*
C5	0.7598 (4)	0.3157 (2)	0.7415 (2)	0.0265 (6)
C6	0.5738 (4)	0.2752 (2)	0.7108 (2)	0.0287 (7)
H6A	0.5573	0.2140	0.7368	0.034*
C7	0.2496 (4)	0.2788 (2)	0.6146 (2)	0.0262 (6)
C8	0.2256 (5)	0.1806 (2)	0.6308 (3)	0.0442 (9)
H8A	0.3310	0.1398	0.6634	0.053*
C9	0.0487 (5)	0.1429 (3)	0.5996 (3)	0.0530 (11)
H9A	0.0340	0.0758	0.6111	0.064*
C10	−0.1092 (4)	0.1998 (2)	0.5515 (3)	0.0368 (8)
C11	−0.0829 (4)	0.2962 (2)	0.5328 (2)	0.0302 (7)
H11A	−0.1883	0.3364	0.4983	0.036*
C12	0.0946 (4)	0.3355 (2)	0.5634 (2)	0.0279 (7)
H12A	0.1094	0.4018	0.5491	0.033*
C13	−0.3033 (5)	0.1564 (3)	0.5204 (3)	0.0522 (10)
H13A	−0.3205	0.1371	0.5821	0.063*
H13B	−0.3971	0.2072	0.4854	0.063*
C14	−0.3384 (6)	0.0684 (3)	0.4514 (3)	0.0581 (11)
H14A	−0.4675	0.0465	0.4307	0.087*
H14B	−0.2532	0.0156	0.4876	0.087*
H14C	−0.3170	0.0862	0.3913	0.087*

	U11	U22	U33	U12	U13	U23
Cu1	0.0276 (2)	0.01543 (19)	0.0310 (2)	−0.00135 (14)	0.01221 (17)	0.00164 (14)
Cl1	0.0399 (4)	0.0189 (4)	0.0290 (4)	−0.0081 (3)	0.0116 (3)	0.0005 (3)
Cl2	0.0375 (4)	0.0188 (4)	0.0416 (4)	−0.0010 (3)	0.0214 (4)	−0.0044 (3)
N1	0.0276 (13)	0.0190 (12)	0.0258 (13)	−0.0006 (11)	0.0116 (11)	0.0015 (10)
N2	0.0259 (13)	0.0171 (12)	0.0258 (13)	−0.0004 (10)	0.0113 (10)	−0.0018 (10)
C1	0.0290 (16)	0.0277 (16)	0.0307 (17)	−0.0014 (13)	0.0127 (14)	0.0044 (13)
C2	0.0263 (16)	0.0390 (18)	0.0329 (18)	−0.0026 (15)	0.0114 (14)	0.0017 (14)
C3	0.0287 (17)	0.0326 (17)	0.0346 (18)	0.0042 (14)	0.0074 (14)	0.0065 (14)
C4	0.0360 (18)	0.0232 (15)	0.0378 (18)	0.0020 (15)	0.0094 (15)	0.0050 (14)
C5	0.0298 (16)	0.0205 (14)	0.0299 (16)	0.0022 (13)	0.0127 (13)	0.0014 (12)
C6	0.0322 (17)	0.0186 (14)	0.0345 (17)	0.0005 (13)	0.0127 (14)	0.0043 (13)
C7	0.0268 (15)	0.0233 (15)	0.0298 (16)	−0.0013 (13)	0.0126 (13)	0.0006 (12)
C8	0.0275 (18)	0.0250 (17)	0.069 (3)	0.0008 (15)	0.0081 (17)	0.0166 (17)
C9	0.0330 (19)	0.0299 (19)	0.082 (3)	−0.0036 (16)	0.009 (2)	0.0176 (19)
C10	0.0278 (17)	0.0346 (19)	0.047 (2)	−0.0026 (15)	0.0136 (15)	0.0002 (15)
C11	0.0265 (16)	0.0283 (16)	0.0328 (17)	0.0048 (13)	0.0090 (14)	−0.0013 (13)
C12	0.0300 (16)	0.0193 (14)	0.0317 (17)	0.0016 (13)	0.0097 (13)	0.0000 (12)
C13	0.033 (2)	0.042 (2)	0.076 (3)	−0.0026 (17)	0.0158 (19)	0.004 (2)
C14	0.048 (2)	0.072 (3)	0.048 (2)	−0.023 (2)	0.0130 (19)	−0.003 (2)

Cu1—N2	2.037 (2)	C6—H6A	0.9500
Cu1—N1	2.079 (2)	C7—C12	1.379 (4)
Cu1—Cl2	2.2876 (8)	C7—C8	1.393 (4)
Cu1—Cl1	2.3067 (8)	C8—C9	1.375 (5)
Cu1—Cl1i	2.4321 (8)	C8—H8A	0.9500
Cl1—Cu1i	2.4321 (8)	C9—C10	1.389 (5)
N1—C1	1.328 (4)	C9—H9A	0.9500
N1—C5	1.350 (4)	C10—C11	1.382 (4)
N2—C6	1.280 (4)	C10—C13	1.523 (5)
N2—C7	1.437 (4)	C11—C12	1.388 (4)
C1—C2	1.390 (4)	C11—H11A	0.9500
C1—H1A	0.9500	C12—H12A	0.9500
C2—C3	1.374 (4)	C13—C14	1.520 (6)
C2—H2A	0.9500	C13—H13A	0.9900
C3—C4	1.384 (4)	C13—H13B	0.9900
C3—H3A	0.9500	C14—H14A	0.9800
C4—C5	1.383 (4)	C14—H14B	0.9800
C4—H4A	0.9500	C14—H14C	0.9800
C5—C6	1.453 (4)
N2—Cu1—N1	80.94 (9)	N2—C6—H6A	119.9
N2—Cu1—Cl2	94.43 (7)	C5—C6—H6A	119.9
N1—Cu1—Cl2	119.40 (7)	C12—C7—C8	119.1 (3)
N2—Cu1—Cl1	171.55 (7)	C12—C7—N2	119.5 (3)
N1—Cu1—Cl1	93.80 (7)	C8—C7—N2	121.4 (3)
Cl2—Cu1—Cl1	93.91 (3)	C9—C8—C7	119.7 (3)
N2—Cu1—Cl1i	90.23 (7)	C9—C8—H8A	120.1
N1—Cu1—Cl1i	113.66 (7)	C7—C8—H8A	120.1
Cl2—Cu1—Cl1i	126.81 (3)	C8—C9—C10	122.0 (3)
Cl1—Cu1—Cl1i	85.82 (3)	C8—C9—H9A	119.0
Cu1—Cl1—Cu1i	94.18 (3)	C10—C9—H9A	119.0
C1—N1—C5	118.0 (3)	C11—C10—C9	117.5 (3)
C1—N1—Cu1	130.8 (2)	C11—C10—C13	121.8 (3)
C5—N1—Cu1	111.22 (19)	C9—C10—C13	120.7 (3)
C6—N2—C7	119.9 (2)	C10—C11—C12	121.3 (3)
C6—N2—Cu1	112.36 (19)	C10—C11—H11A	119.3
C7—N2—Cu1	127.69 (18)	C12—C11—H11A	119.3
N1—C1—C2	122.4 (3)	C7—C12—C11	120.3 (3)
N1—C1—H1A	118.8	C7—C12—H12A	119.9
C2—C1—H1A	118.8	C11—C12—H12A	119.9
C3—C2—C1	119.5 (3)	C14—C13—C10	113.4 (3)
C3—C2—H2A	120.3	C14—C13—H13A	108.9
C1—C2—H2A	120.3	C10—C13—H13A	108.9
C2—C3—C4	118.6 (3)	C14—C13—H13B	108.9
C2—C3—H3A	120.7	C10—C13—H13B	108.9
C4—C3—H3A	120.7	H13A—C13—H13B	107.7
C5—C4—C3	118.7 (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	122.8 (3)	C13—C14—H14C	109.5
N1—C5—C6	115.0 (3)	H14A—C14—H14C	109.5
C4—C5—C6	122.2 (3)	H14B—C14—H14C	109.5
N2—C6—C5	120.3 (3)
N2—Cu1—Cl1—Cu1i	62.3 (5)	Cu1—N1—C5—C4	−179.1 (2)
N1—Cu1—Cl1—Cu1i	113.48 (7)	C1—N1—C5—C6	−179.5 (3)
Cl2—Cu1—Cl1—Cu1i	−126.67 (3)	Cu1—N1—C5—C6	2.2 (3)
Cl1i—Cu1—Cl1—Cu1i	0.0	C3—C4—C5—N1	1.7 (5)
N2—Cu1—N1—C1	178.7 (3)	C3—C4—C5—C6	−179.7 (3)
Cl2—Cu1—N1—C1	−91.4 (3)	C7—N2—C6—C5	176.6 (3)
Cl1—Cu1—N1—C1	5.3 (3)	Cu1—N2—C6—C5	−4.4 (4)
Cl1i—Cu1—N1—C1	92.4 (3)	N1—C5—C6—N2	1.5 (4)
N2—Cu1—N1—C5	−3.39 (19)	C4—C5—C6—N2	−177.3 (3)
Cl2—Cu1—N1—C5	86.6 (2)	C6—N2—C7—C12	168.0 (3)
Cl1—Cu1—N1—C5	−176.73 (19)	Cu1—N2—C7—C12	−10.8 (4)
Cl1i—Cu1—N1—C5	−89.63 (19)	C6—N2—C7—C8	−12.8 (4)
N1—Cu1—N2—C6	4.2 (2)	Cu1—N2—C7—C8	168.4 (3)
Cl2—Cu1—N2—C6	−114.9 (2)	C12—C7—C8—C9	−2.7 (5)
Cl1—Cu1—N2—C6	56.1 (6)	N2—C7—C8—C9	178.1 (3)
Cl1i—Cu1—N2—C6	118.1 (2)	C7—C8—C9—C10	0.1 (6)
N1—Cu1—N2—C7	−176.9 (2)	C8—C9—C10—C11	2.1 (6)
Cl2—Cu1—N2—C7	64.0 (2)	C8—C9—C10—C13	−178.3 (4)
Cl1—Cu1—N2—C7	−125.0 (4)	C9—C10—C11—C12	−1.8 (5)
Cl1i—Cu1—N2—C7	−63.0 (2)	C13—C10—C11—C12	178.6 (3)
C5—N1—C1—C2	−0.4 (4)	C8—C7—C12—C11	2.9 (5)
Cu1—N1—C1—C2	177.5 (2)	N2—C7—C12—C11	−177.8 (3)
N1—C1—C2—C3	0.6 (5)	C10—C11—C12—C7	−0.7 (5)
C1—C2—C3—C4	0.3 (5)	C11—C10—C13—C14	123.0 (4)
C2—C3—C4—C5	−1.4 (5)	C9—C10—C13—C14	−56.6 (5)
C1—N1—C5—C4	−0.8 (4)

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···Cl1	0.95	2.80	3.364 (3)	119
C2—H2A···Cl2ii	0.95	2.76	3.445 (3)	130
C6—H6A···Cl2iii	0.95	2.62	3.506 (3)	155
C12—H12A···Cl2	0.95	2.80	3.450 (3)	126

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1A⋯Cl1	0.95	2.80	3.364 (3)	119
C2—H2A⋯Cl2i	0.95	2.76	3.445 (3)	130
C6—H6A⋯Cl2ii	0.95	2.62	3.506 (3)	155
C12—H12A⋯Cl2	0.95	2.80	3.450 (3)	126

Symmetry codes: (i) ; (ii) .