The dinuclear copper(II) complexes di -μ Chlorido-bis-{[N,N′-bis- (4-chloro-benz-yl)propane-1,2-diamine]chloridocopper(II)} and di -μ Chlorido-bis-{[N,N′-bis-(3,4-methyl-enedioxybenzyl)-prop-ane-1,2-diamine] chloridocopper(II)}

Article abstract of DOI:10.1107/S0108270107058519

The two title dinuclear copper(II) complexes, [Cu2Cl4(C17H20Cl2N2)2], (I), and [Cu2Cl4(C19H22N2O4)2], (II), have similar coordination environments. In each complex, the asymmetric unit consists of one half-mol-ecule and the two copper centres are bridged by a pair of Cl atoms, resulting in complexes with centrosymmetric structures containing Cu(-Cl)2Cu paral-lelogram cores; the Cu...Cu separations and Cu - Cl - Cu angles are 3.4285 (8) A and 83.36 (3)°, respectively, for (I), and 3.565 (2) A and 84.39 (7)° for (II). Each Cu atom is five-coordinated and the coordination geometry around the Cu atom is best described as a distorted square-pyramid with a value of 0.155 (3) for (I) and 0.092 (7) for (II). The apical Cu - -Cl bond length is 2.852 (1) A for (I) and 2.971 (2) A for (II). The basal Cu - Cl and Cu - N average bonds lengths are 2.2673 (9) and 2.030 (2) A, respectively, for (I), and 2.280 (2) and 2.038 (6) A for (II). The mol-ecules of (I) are linked by one C - H...Cl hydrogen bond into a complex [10 ] sheet. The mol-ecules of (II) are linked by one C - H...Cl and one N - H...O hydrogen bond into a complex [100] sheet. International Union of Crystallography 2007.

Full text of DOI:10.1107/S0108270107058519

metal-organic compounds
Acta Crystallographica Section C
Crystal Structure
Communications
used as bridging ligands (Christou et al., 2000). Many
dichloride-bridged dinuclear copper systems have been
reported in the literature and different magnetic behaviours
ISSN 0108-2701
The dinuclear copper(II) complexes
di-l-chlorido-bis{[N,N0-bis(4-chloro-
benzyl)propane-1,2-diamine]chlorido-
copper(II)} and di-l-chlorido-bis{[N,N0-
bis(3,4-methylenedioxybenzyl)prop-
ane-1,2-diamine]chloridocopper(II)}
Shu-Ping Yang,a* Li-Jun Han,b Hai-Tao Xia,a Da-Qi Wangc
and Yu-Fen Liua
aDepartment of Chemical Engineering, Huaihai Institute of Technology, Lianyungang
222005, People's Republic of China, bDepartment of Mathematics and Science,
Huaihai Institute of Technology, Lianyungang 222005, People's Republic of China,
and cCollege of Chemistry and Chemical Engineering, Liaocheng University,
Shandong 252059, People's Republic of China
Correspondence e-mail: yangshuping@hhit.edu.cn
Received 27 October 2007
Accepted 13 November 2007
Online 30 November 2007
Â
observed (Rodrõguez et al., 2000; Schuitema et al., 2002; Tuna
The two title dinuclear copper(II) complexes, [Cu2Cl4(C17H20-
Cl2N2)2], (I), and [Cu2Cl4(C19H22N2O4)2], (II), have similar
coordination environments. In each complex, the asymmetric
unit consists of one half-molecule and the two copper centres
are bridged by a pair of Cl atoms, resulting in complexes with
centrosymmetric structures containing Cu(ꢀ-Cl)2Cu paral-
lelogram cores; the CuÁ Á ÁCu separations and CuÐClÐCu
et al., 1999), and the magneto-structural correlation, which
relates the magnetic interaction to '/R (as de®ned below), has
been established (Marsh et al., 1982). Copper complexes
containing diimines have also been extensively studied and
reported owing to their potential applications (Alvesa et al.,
2004). Previously, our group has reported the structures of
some transition metal complexes with diimines (Han et al.,
2006; Liu et al., 2007; Xia et al., 2007; Yang et al., 2007). For this
reason, we have synthesized two new dichloride-bridged
dinuclear copper complexes with diimines, di-ꢀ-chlorido-
ꢀ
Ê
angles are 3.4285 (8) A and 83.36 (3) , respectively, for (I),
ꢀ
Ê
and 3.565 (2) A and 84.39 (7) for (II). Each Cu atom is ®ve-
coordinated and the coordination geometry around the Cu
atom is best described as a distorted square-pyramid with a ꢁ
value of 0.155 (3) for (I) and 0.092 (7) for (II). The apical
Ê
Ê
CuÐCl bond length is 2.852 (1) A for (I) and 2.971 (2) A for
(II). The basal CuÐCl and CuÐN average bonds lengths are
Ê
2.2673 (9) and 2.030 (2) A, respectively, for (I), and 2.280 (2)
Ê
and 2.038 (6) A for (II). The molecules of (I) are linked by one
CÐHÁ Á ÁCl hydrogen bond into a complex [101] sheet. The
molecules of (II) are linked by one CÐHÁ Á ÁCl and one NÐ
HÁ Á ÁO hydrogen bond into a complex [100] sheet.
Comment
Dinuclear transition metal complexes have received much
attention because of their relevance as models for active sites
of biomolecules, such as hemocyanin, tyrosinase and copper
oxidases (Pradeep et al., 2005; Sorrell, 1989), and also because
of the correlation between their structure and magnetic
Â
behaviour (Schuitema et al., 2002; Rodrõguez et al., 2000).
Among these dinuclear transition metal complexes, some
anions, such as OH , RO , RCO2 , Cl and Br , are often
Figure 1
The molecule of (I), showing the atom-labelling scheme. Displacement
ellipsoids are drawn at the 30% probability level. For clarity, H atoms
have been omitted. Dashed lines indicate hydrogen bonds. [Symmetry
code: (i) x + 1, y + 1, z + 1.]
m610 # 2007 International Union of Crystallography
DOI: 10.1107/S0108270107058519
Acta Cryst. (2007). C63, m610±m614

metal-organic compounds
bis{[N,N0-bis(4-chlorobenzyl)propane-1,2-diamine]chlorido-
copper(II)}, (I), and di-ꢀ-chlorido-bis{[N,N0-bis(3,4-methyl-
enedioxybenzyl)propane-1,2-diamine]chloridocopper(II)}, (II),
whose syntheses and structures are reported here.
pyrazole)2Cl4], (III) [CuÁ Á ÁCu = 3.479 (4) A; Schuitema et al.,
Ê
2002], and {[CuL2Cl2]2[ClO4]2}, (IV) [where L is 1-(imidazol-
Ê
4-ylmethyl)-l,5-diazacyclooctane; CuÁ Á ÁCu = 3.494 (8) A; Bu
et al., 2001], in which magnetic coupling between the copper
centres can be observed; however, the CuÁ Á ÁCu separation of
Complexes (I) and (II) have similar coordination environ-
ments (Figs. 1 and 2). In each complex, the asymmetric unit
consists of one half-molecule; two copper centres are bridged
by a pair of Cl atoms, resulting in a complex with a centro-
symmetric structure containing a Cu(ꢀ-Cl)2Cu parallelogram
Ê
3.565 (2) A for (II) is longer than those of (III) and (IV). The
CuÐClÐCu angles are 83.36 (3)ꢀ for (I) and 84.39 (7)ꢀ for
(II); these values are smaller than those of (III) and (IV), in
which the CuÐClÐCu angles range from 85.33 (15) to
88.81 (5)ꢀ. Each Cu atom in (I) and (II) is ®ve-coordinated by
two N atoms of one ligand and three Cl atoms, and the
coordination polyhedron around the Cu atom may be
described as a slightly distorted square pyramid with ꢁ values
(Addison et al., 1984) of 0.155 (3) for (I) and 0.092 (7) for (II),
where ꢁ is de®ned as (ꢂ ꢃ)/60, and ꢂ and ꢃ are the largest
coordination angles (ꢁ = 0 for a regular square-pyramidal
geometry and ꢁ = 1 for trigonal-bipyramidal geometry). The
apical position is occupied by one elongated bridging Cl atom,
Ê
core. The CuÁ Á ÁCu separation of 3.4285 (8) A for (I) is smaller
than those values reported in two dichloride-bridged dinuclear
copper(II) complexes, viz. [Cu2(5-aminomethyl-3-methyl-
Ê
and the apical CuÐCl bond distances are 2.852 (1) A for (I)
Ê
and 2.971 (2) A for (II); these values are longer than those of
(III) and (IV), in which the apical CuÐCl bond distances
Ê
range from 2.6571 (14) to 2.829 (4) A. The basal planes are
de®ned by atoms Cl1, Cl2, N1 and N2; atoms Cu1 are shifted
Ê
Ê
by 0.106 (1) A for (I) and 0.050 (3) A for (II) from the basal
planes toward the apical Cl1A atom. The basal CuÐCl and
Ê
CuÐN average bond lengths are 2.2673 (9) and 2.030 (2) A
Ê
in (I), and 2.280 (2) and 2.038 (6) A in (II) (see in Tables 1
and 3).
Generally, dichloride-bridged dinuclear copper complexes
with square-pyramidal geometry exhibit three different
geometries with regard to the relative arrangement of square
pyramids, viz. perpendicular bases (type I), parallel bases
Figure 2
The molecule of (II), showing the atom-labelling scheme. Displacement
ellipsoids are drawn at the 30% probability level. For clarity, H atoms
have been omitted. Dashed lines indicate hydrogen bonds. [Symmetry
code: (i) x + 1, y + 1, z + 1.]
Figure 3
Part of the crystal structure of (I), showing the formation of a [101] sheet. For clarity, H atoms have been omitted. Dashed lines indicate hydrogen bonds.
3
2
1
2
3
[Symmetry code: (ii) x + , y
,
z + .]
2
ꢁ
Acta Cryst. (2007). C63, m610±m614
Yang et al.
[Cu2Cl4(C17H20Cl2N2)2] and [Cu2Cl4(C19H22N2O4)2] m611

metal-organic compounds
Figure 4
Part of the crystal structure of (II), showing the formation of a [100] sheet. For clarity, H atoms have been omitted. Dashed lines indicate hydrogen bonds.
1
2
1
[Symmetry code: (ii) x + 1, y
,
z + .]
2
Â
(type II) and coplanar bases (type III) (Rodrõguez et al., 2000).
In the parallel bases case, two square pyramids share a base-
to-apex edge, so that a Cl atom situated at the vertex of one
base becomes the apical vertex of the other square pyramid.
The symmetric arrangements of the Cu(ꢀ-Cl)2Cu cores in
complexes (I) and (II) belong to type II. The two intra-
molecular basal planes are strictly parallel, with interplanar
bond; atom C11 at (x, y, z) in the molecule centred at (12, 21, 21 )
acts as a hydrogen-bond donor, via H11B, to atom Cl2 at
1
( x + 32, y
,
z + 32 ) in the molecule centred at (1, 0, 1), and
2
propagation is via inversion, the screw axis and translation
generating a complex sheet in [101] (Fig. 3 and Table 2).
In (II), the molecules are linked by one intermolecular CÐ
HÁ Á ÁCl and one NÐHÁ Á ÁO hydrogen bond; atoms C12 and N2
at (x, y, z) in the molecule centred at (12, 21, 21 ) act as hydrogen-
Ê
Ê
spacings of 2.731 (6) A for (I) and 2.82 (3) A for (II), corre-
Ê
Ê
sponding to plane offsets of 2.07 (1) A for (I) and 2.18 (4) A
for (II); the dihedral angles between the Cu(ꢀ-Cl)2Cu paral-
lelogram core and the basal plane are 87.27 (4)ꢀ for (I) and
86.85 (8)ꢀ for (II).
bond donors, via H12A and H2, to atoms Cl2 and O3 at ( x + 1,
1
y
,
z + 12 ) in the molecule centred at (1, 0, 1), and
propagation via a screw axis and translation generates a
complex sheet in [100] (Fig. 4 and Table 4).
2
Some theoretical analysis and experiments concerning the
magneto-structural correlation for dichloride-bridged di-
nuclear copper(II) complexes can be found in the literature
Experimental
For the preparation of complex (I), a solution of copper chloride
(0.48 g, 3 mmol) in ethanol (10 ml) was added dropwise with stirring
to a solution of N,N-bis(4-chlorobenzyl)propane-1,2-diamine (0.96 g,
3 mmol) in ethanol (20 ml). The reaction mixture was stirred for 3 h
at 333±343 K and then left to cool at room temperature; the solid
obtained was ®ltered off, washed successively with chloroform
(3 Â 3 ml) and ethanol (3 Â 3 ml), and dried at room temperature.
Green crystals of (I) suitable for X-ray structure analysis were
obtained by slow evaporation of a dimethylformamide±ethanol (1:10)
solution containing the product over a period of three weeks (yield
0.98 g, 68%; m.p. 466±469 K). Analysis calculated for C34H40Cl8-
Cu2N4: C 44.61, H 4.40, N 6.12%; found: C 45.22, H 4.28, N 5.88%. IR
(KBr, cm 1): 3450, 3162, 2946, 1599, 1551, 1492, 1440, 1089, 1013, 922,
810, 704, 566.
Â
(Schuitema et al., 2002; Rodrõguez et al., 2000; Tuna et al.,
1999). Marsh et al. (1982) have shown that the exchange
coupling interaction depends on the magnitude of the angle at
the CuÐClÐCu bridge, ', as well as the apical CuÐCl bond
length, R. It was found that, for values of the quotient '/R that
1
are lower than 32.6 A and higher than 34.88 A 1, the
exchange interaction is antiferromagnetic. For values falling
between these limits, the exchange interaction was found to be
ferromagnetic. In the cases of (I) and (IIꢀ), the values of the
ꢀ
ꢀ
Ê
Ê
quotient '/R are 29.23 (2) and 28.40 (4) A 1, respectively;
both quotients are below the border value of 32.6ꢀ
Ê
1
Ê
A
,
suggesting an antiferromagnetic interaction between the two
copper(II) ions.
In the crystal structures of (I) and (II), the molecules are
stabilized by a pair of intramolecular NÐHÁ Á ÁCl hydrogen
bonds (Figs. 1 and 2, and Tables 2 and 4). In (I), the molecules
are linked by a single intermolecular CÐHÁ Á ÁCl hydrogen
Using the same method, green crystals of complex (II) suitable for
X-ray structure analysis were also obtained (yield 1.18 g, 71%; m.p.
509±512 K). Analysis calculated for C38H44Cl4Cu2N4O8: C 47.86, H
4.65, N 5.87%; found: C 48.48, H 4.49, N 6.02%. IR (KBr disk, cm 1):
3464, 3250, 2932, 1599, 1553, 1493,1447, 1252, 1034, 922, 812, 767, 704.
ꢁ
m612 Yang et al. [Cu2Cl4(C17H20Cl2N2)2] and [Cu2Cl4(C19H22N2O4)2]
Acta Cryst. (2007). C63, m610±m614

metal-organic compounds
Re®nement
Compound (I)
R[F2 > 2ꢄ(F2)] = 0.063
wR(F2) = 0.217
S = 1.14
254 parameters
H-atom parameters constrained
Crystal data
3
3
Ê
Ê
V = 1938.2 (4) A
Áꢅmax = 1.12 e A
[Cu2Cl4(C17H20Cl2N2)2]
Mr = 915.38
3
Ê
0.64 e A
3730 re¯ections
Áꢅmin
=
Z = 2
Mo Kꢃ radiation
Monoclinic, P21=n
1
Ê
a = 14.4217 (15) A
ꢀ = 1.68 mm
T = 298 (2) K
Ê
b = 9.5445 (13) A
Table 3
Selected geometric parameters (A, ) for (II).
ꢀ
Ê
Ê
c = 15.6198 (19) A
ꢂ = 115.647 (2)ꢀ
0.54 Â 0.50 Â 0.46 mm
Cu1ÐN1
Cu1ÐN2
Cu1ÐCl2
2.032 (6)
2.044 (6)
2.278 (2)
Cu1ÐCl1
Cu1ÐCl1i
Cu1ÐCu1i
2.282 (2)
2.971 (2)
3.565 (2)
Data collection
Bruker SMART CCD area-detector
diffractometer
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
Tmin = 0.464, Tmax = 0.512
(expected range = 0.418±0.462)
8896 measured re¯ections
3417 independent re¯ections
2484 re¯ections with I > 2ꢄ(I)
Rint = 0.038
N1ÐCu1ÐN2
N1ÐCu1ÐCl2
N2ÐCu1ÐCl2
N1ÐCu1ÐCl1
N2ÐCu1ÐCl1
Cl2ÐCu1ÐCl1
84.5 (2)
170.0 (2)
92.1 (2)
90.4 (2)
164.3 (2)
95.26 (8)
N1ÐCu1ÐCl1i
N2ÐCu1ÐCl1i
Cl2ÐCu1ÐCl1i
Cl1ÐCu1ÐCl1i
Cu1ÐCl1ÐCu1i
81.5 (2)
98.3 (2)
89.70 (7)
95.61 (7)
84.39 (7)
Re®nement
R[F2 > 2ꢄ(F2)] = 0.031
wR(F2) = 0.082
S = 1.06
218 parameters
H-atom parameters constrained
Symmetry code: (i) x ‡ 1; y ‡ 1; z ‡ 1.
3
Ê
Áꢅmax = 0.39 e A
3
Ê
0.28 e A
3417 re¯ections
Áꢅmin
=
Table 4
Hydrogen-bond geometry (A, ) for (II).
ꢀ
Ê
Table 1
Selected geometric parameters (A, ) for (I).
ꢀ
Ê
DÐHÁ Á ÁA
DÐH
HÁ Á ÁA
DÁ Á ÁA
DÐHÁ Á ÁA
Cu1ÐN1
Cu1ÐN2
Cu1ÐCl1
2.026 (2)
2.033 (2)
2.2604 (9)
Cu1ÐCl2
Cu1ÐCl1i
Cu1ÐCu1i
2.2742 (9)
2.852 (1)
3.4285 (8)
N1ÐH1Á Á ÁCl2i
0.91
0.91
0.97
0.97
2.58
2.20
2.84
2.87
3.476 (6)
3.075 (9)
3.774 (8)
3.779 (11)
169
160
162
156
N2ÐH2Á Á ÁO3ii
C12ÐH12AÁ Á ÁCl2ii
C11ÐH11AÁ Á ÁCl1iii
N1ÐCu1ÐN2
N1ÐCu1ÐCl1
N2ÐCu1ÐCl1
N1ÐCu1ÐCl2
N2ÐCu1ÐCl2
83.69 (9)
92.41 (7)
159.84 (8)
169.01 (7)
90.49 (7)
Cl1ÐCu1ÐCl2
N1ÐCu1ÐCl1i
N2ÐCu1ÐCl1i
Cl1ÐCu1ÐCl1i
Cl2ÐCu1ÐCl1i
96.18 (3)
82.32 (7)
102.40 (7)
96.64 (3)
89.87 (3)
1
2
Symmetry codes: (i) x ‡ 1; y ‡ 1; z ‡ 1; (ii) x ‡ 1; y
y ‡ 1; z ‡ 1.
;
z ‡ 12; (iii) x ‡ 2,
Symmetry code: (i) x ‡ 1; y ‡ 1; z ‡ 1.
All H atoms were located in difference Fourier maps and treated
as riding atoms, with CÐH distances of 0.98 (methine), 0.93 (aryl),
Ê
Ê
0.96 (methyl) and 0.97 A (methylene), NÐH distances of 0.91 A, and
Uiso(H) values of 1.2Ueq(methine, aryl and methylene C, and imine
N) and 1.5Ueq(methyl C). The value of Rint for complex (II) is high
because of the poor crystal quality, resulting in broad diffraction
peaks.
Table 2
Hydrogen-bond geometry (A, ) for (I).
ꢀ
Ê
DÐHÁ Á ÁA
DÐH
HÁ Á ÁA
DÁ Á ÁA
DÐHÁ Á ÁA
N1ÐH1Á Á ÁCl2i
C13ÐH13Á Á ÁCl3iii
Symmetry codes: (i) x ‡ 1; y ‡ 1; z ‡ 1; (ii) x ‡ 32; y
z ‡ 32.
0.91
0.97
0.93
2.57
2.82
2.89
3.450 (3)
3.659 (3)
3.810 (3)
164
145
170
For both compounds, data collection: SMART (Siemens, 1996);
cell re®nement: SAINT (Siemens, 1996); data reduction: SAINT;
program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a);
program(s) used to re®ne structure: SHELXL97 (Sheldrick, 1997a);
molecular graphics: SHELXTL (Sheldrick, 1997b); software used to
prepare material for publication: SHELXTL.
C11ÐH11BÁ Á ÁCl2ii
z ‡ 32; (iii) x ‡ 12, y
,
1
;
2
1
2
Compound (II)
We acknowledge the ®nancial support of the Huaihai
Institute of Technology Science Foundation.
Crystal data
3
Ê
[Cu2Cl4(C19H22N2O4)2]
Mr = 953.65
V = 2129.2 (4) A
Z = 2
Supplementary data for this paper are available from the IUCr electronic
archives (Reference: HJ3060). Services for accessing these data are
described at the back of the journal.
Monoclinic, P21=c
Mo Kꢃ radiation
ꢀ = 1.30 mm
T = 298 (2) K
0.45 Â 0.37 Â 0.31 mm
1
Ê
a = 12.2965 (13) A
Ê
b = 11.0554 (12) A
Ê
c = 15.822 (2) A
ꢂ = 98.140 (2)ꢀ
References
Data collection
Bruker SMART CCD area-detector
diffractometer
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
Tmin = 0.592, Tmax = 0.688
10028 measured re¯ections
3730 independent re¯ections
2008 re¯ections with I > 2ꢄ(I)
Rint = 0.162
Addison, A. W., Rao, T. N., Reedijk, J., Rijn, J. V. & Verschoor, G. C. (1984). J.
Chem. Soc. Dalton Trans. pp. 1349±1356.
Alvesa, W. A., de Almeida-Filhoa, S. A., de Almeida Santosb, R. H., Paduan-
Filhoc, A. & da Costa Ferreira, A. M. (2004). J. Braz. Chem. Soc. 15, 872±
883.
ꢁ
Acta Cryst. (2007). C63, m610±m614
Yang et al.
[Cu2Cl4(C17H20Cl2N2)2] and [Cu2Cl4(C19H22N2O4)2] m613

metal-organic compounds
È
Sheldrick, G. M. (1996). SADABS. University of Gottingen, Germany.
Sheldrick, G. M. (1997a). SHELXS97 and SHELXL97. University of
Bu, X.-H., Du, M., Zhang, L., Shang, Z.-L., Ruo-Hua Zhang, R.-H. &
Shionoya, M. (2001). J. Chem. Soc. Dalton Trans. pp. 729±735.
Christou, G., Gatteschi, D. N., Hendrickson, D. N. & Sessoli, R. (2000). MRS
Bull. 25, 66±71.
Han, L.-J., Yang, S.-P., Wang, D.-Q. & Xia, H.-T. (2006). Acta Cryst. E62,
m2607±m2609.
È
Gottingen, Germany.
Sheldrick, G. M. (1997b). SHELXTL. Version 5.1. Bruker AXS Inc., Madison,
Wisconsin, USA.
Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments
Inc., Madison, Wisconsin, USA.
Sorrell, T. N. (1989). Tetrahedron, 45, 3±68.
Liu, Y.-F., Xia, H.-T., Yang, S.-P. & Wang, D.-Q. (2007). Acta Cryst. E63, m332±
m334.
Marsh, W. E., Hat®eld, W. E. & Hodgson, D. J. (1982). Inorg. Chem. 21, 2679±
2684.
Pradeep, C. P., Zacharias, P. S. & Das, S. K. (2005). J. Chem. Sci. 117, 133±137.
Tuna, F., Patron, L., Journaux, Y., Andruh, M., Plass, W. & Trombee, J.-C.
(1999). J. Chem. Soc. Dalton Trans. pp. 539±545.
Xia, H.-T., Liu, Y.-F., Wang, D.-Q. & Yang, S.-P. (2007). Acta Cryst. E63,
m1162±m1164.
Â
Rodrõguez, M., Llobet, A. & Corbella, M. (2000). Polyhedron, 19, 2483±2491.
Schuitema, A. M., Stassen, A. F., Driessen, W. L. & Reedijk, J. (2002). Inorg.
Chim. Acta, 337, 48±52.
Yang, S.-P., Han, L.-J., Wang, D.-Q. & Xia, H.-T. (2007). Acta Cryst. E63,
m2763.
ꢁ
m614 Yang et al. [Cu2Cl4(C17H20Cl2N2)2] and [Cu2Cl4(C19H22N2O4)2]
Acta Cryst. (2007). C63, m610±m614