Bis(μ-benzene-1,2-dicarboxyl-ato)-bis{aqua-[2-(2-chloro-6-fluorophenyl) -1H-imidazo[4,5-f][1,10]phen-an-thro-line]cadmium(II)} and its zinc(II) analogue

Article abstract of DOI:10.1107/S0108270109044886

In the isomorphous title compounds, [Cd₂(C₈H ₄O₄)2(C₁₉H_10-ClFN₄) ₂(H₂O)₂] and [Zn₂(C ₈H₄O₄)₂

Full text of DOI:10.1107/S0108270109044886

metal-organic compounds
Acta Crystallographica Section C
Crystal Structure
Communications
used to construct varied supramolecular architectures (Wang
et al., 2007). To date, much research has focused on controlling
motifs of metal–organic complexes through coordination
bonds. However, less attention has been given to noncovalent
ꢀ–ꢀ interactions (Yang et al., 2009). The ꢀ–ꢀ interaction can
be one of the most powerful noncovalent intermolecular
interactions for directing supramolecular architectures (Yang
et al., 2007; Qiao et al., 2009). In particular, conjugated ꢀ
systems can strongly influence the physical properties of
coordination compounds. Therefore, the design of versatile
functional ligands that are capable of coordinating to a metal
atom while providing the ꢀ-conjugated system for organizing
their complexes into extended networks through ꢀ–ꢀ inter-
actions is quite desirable. So far, the 1,10-phenanthroline
ligand has been widely used to construct supramolecular
architectures owing to its excellent coordinating ability and
large conjugated system that can easily form ꢀ–ꢀ interactions.
However, derivatives such as 2-(2-chloro-6-fluorophenyl)-1H-
imidazo[4,5-f][1,10]phenanthroline (L), which is a good
candidate for the construction of metal–organic supra-
molecular architectures, have received far less attention
(Wang et al., 2007). On the other hand, carboxylate-based
ligands have been successfully employed in the generation of
many interesting coordination compounds (Ockwig et al.,
2005). In this contribution, we selected benzene-1,2-di-
carboxylate (1,2-bdc) as an organic linker and L as an N-donor
chelating ligand, generating two isomorphous coordination
compounds, [Cd(1,2-bdc)(L)(H2O)]2, (I), and [Zn(1,2-bdc)-
(L)(H2O)]2, (II).
ISSN 0108-2701
Bis(l-benzene-1,2-dicarboxylato)-
bis{aqua[2-(2-chloro-6-fluorophenyl)-
1H-imidazo[4,5-f][1,10]phenanthro-
line]cadmium(II)} and its zinc(II)
analogue
Xiu-Yan Wang,a* Ming Wanga and Xiao-Yuan Mab
aCollege of Chemistry, Jilin Normal University, Siping 136000, People’s Republic of
China, and bSiping Academy of Science and Technology, Siping 36000, People’s
Republic of China
Correspondence e-mail: wangxiuyan2001@yahoo.com.cn
Received 16 August 2009
Accepted 27 October 2009
Online 7 November 2009
In the isomorphous title compounds, [Cd2(C8H4O4)2(C19H10-
ClFN4)2(H2O)2] and [Zn2(C8H4O4)2(C19H10ClFN4)2(H2O)2],
the CdII centre is seven-coordinated by two N atoms from one
[2-(2-chloro-6-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenan-
throline (L) ligand, one water O atom and four carboxylate O
atoms from two different benzene-1,2-dicarboxylate (1,2-bdc)
ligands in a distorted pentagonal–bipyramidal coordination,
while the ZnII centre is six-coordinated by two N atoms from
one L ligand, one water O atom and three carboxylate O
atoms from two different 1,2-bdc ligands in a distorted
octahedral coordination. Each pair of adjacent metal centres is
bridged by two 1,2-bdc ligands to form a dimeric structure. In
the dimer, each L ligand coordinates one metal centre. The
dimer is centrosymmetric, with a crystallographic inversion
centre midway between the two metal centres. The aromatic
interactions lead the dimers to form a two-dimensional
supramolecular architecture. Finally, O—Hꢀ ꢀ ꢀO and N—
Hꢀ ꢀ ꢀO hydrogen bonds reinforce the two-dimensional struc-
tures of the two compounds.
Comment
The design and synthesis of discrete and polymeric metal–
organic complexes is currently attracting considerable atten-
tion in view of their interesting structural topologies and
properties (Eddaoudi et al., 2001; Hagrman et al., 1999;
Ockwig et al., 2005). These complexes can be specially
designed by the careful selection of metal cations with
preferred coordination geometries, considering also the
nature of the anions, the structure of the connecting ligands
and the reaction conditions (Wang et al., 2008; Chen et al.,
2008). Usually, two different types of interactions, such as
covalent bonds and noncovalent intermolecular forces, can be
Compounds (I) and (II) are isomorphous and, therefore,
only the structure of (I) will be described in detail. Selected
bond lengths and angles for the two compounds are given in
Tables 1 and 3. As shown in Fig. 1, the CdII centre is seven-
coordinated by two N atoms from one L ligand, one water O
atom and four carboxylate O atoms from two different 1,2-bdc
ligands, in a distorted pentagonal–bipyramidal coordination.
Acta Cryst. (2009). C65, m459–m462
doi:10.1107/S0108270109044886
# 2009 International Union of Crystallography m459

metal-organic compounds
Four O atoms (O1, O2, O3i and O4i; symmetry code as in
Fig. 1) from two 1,2-bdc anions and one N atom (N2) from the
L ligand make up the equatorial plane, while the axial posi-
tions are occupied by one water O atom (O1W) and a second
N atom (N1) from the L ligand. The Cd—O(carboxylate)
second is a C—Hꢀ ꢀ ꢀꢀ interaction between atom C23 of the
1
2
1,2-bdc ligand and a pyridine ring [N2/C6–C10 at (ꢁx, y ꢁ ,
3
2
˚
ꢁz + )] of the L ligand [3.588 (5) A; Fig. 2]. When these
interactions are taken into account, the one-dimensional
supramolecular chains become a two-dimensional supra-
molecular layer. Moreover, there are both N—Hꢀ ꢀ ꢀO and
O—Hꢀ ꢀ ꢀO hydrogen bonds in (I). The N—Hꢀ ꢀ ꢀO hydrogen
bonds join the molecules into one-dimensional chains in the
c-axis direction (along with the reported ꢀ–ꢀ interaction)
(Tables 2 and 4). The supramolecular layers form a three-
dimensional supramolecular architecture through the
N—Hꢀ ꢀ ꢀO and O—Hꢀ ꢀ ꢀO hydrogen bonds.
˚
distances range from 2.314 (2) to 2.484 (2) A, which are
comparable to those found in other crystallographically
characterized CdII complexes (Qiao et al., 2008). Each pair of
adjacent CdII centres is bridged by two 1,2-bdc ligands to form
˚
a dimeric structure with a Cdꢀ ꢀ ꢀCd separation of 4.987 (4) A.
In the dimer, each L ligand coordinates one metal centre. The
dimer is centrosymmetric, with a crystallographic inversion
centre midway between the two CdII centres. Notably, the L
ligands are arranged in a parallel fashion at both sides of a
dimer, leading to a structure capable of aromatic intercalation.
Two types of aromatic interactions between neighbouring
dimers have been found. One is a ꢀ–ꢀ interaction between the
quinoline ring systems [N2/C4–C12 at (x, y, z) and (ꢁx, ꢁy + 1,
ꢁz + 1)] of the L ligands [with a centroid–centroid distance of
Although compounds (I) and (II) are isostructural, their
coordination is slightly different. In (I), the CdII centre is
seven-coordinated by two N atoms from one L ligand, one
water O atom and four carboxylate O atoms from two
different 1,2-bdc ligands, in
a distorted pentagonal–
bipyramidal coordination. Conversely, in (II), the ZnII centre
is six-coordinated by three carboxylate O atoms from two
different 1,2-bdc ligands, one water O atom and two N
atoms from one L ligand, in a distorted octahedral coordina-
tion.
˚
˚
3.854 (3) A, a face-to-face distance of 3.304 (2) A and a
dihedral angle of 0.607 (3)ꢂ], which leads the dimers to form a
one-dimensional supramolecular chain along the c axis. The
Figure 1
A view of the local coordination of the MII cations in (a) (I) (M = Cd) and (b) (II) (M = Mn), showing the atom-numbering schemes. Displacement
ellipsoids are drawn at the 30% probability level and H atoms have been omitted for clarity. [Symmetry code: (i) ꢁx, ꢁy + 1, ꢁz + 2.]
ꢃ
m460 Wang et al. [M2(C8H4O4)2(C19H10ClFN4)2(H2O)2] (M = Cd and Zn)
Acta Cryst. (2009). C65, m459–m462

metal-organic compounds
Compound (I)
Crystal data
[Cd2(C8H4O4)2(C19H10ClFN4)2-
(H2O)2]
Mr = 1286.58
ꢁ = 105.479 (1)ꢂ
3
˚
V = 2504.8 (3) A
Z = 2
Monoclinic, P21=c
Mo Kꢂ radiation
ꢃ = 1.03 mmꢁ1
T = 293 K
0.27 ꢄ 0.22 ꢄ 0.20 mm
˚
a = 8.7749 (7) A
b = 21.8204 (17) A
˚
˚
c = 13.5740 (11) A
Data collection
Bruker APEX diffractometer
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
Tmin = 0.752, Tmax = 0.811
13862 measured reflections
4944 independent reflections
3703 reflections with I > 2ꢄ(I)
Rint = 0.030
Refinement
R[F2 > 2ꢄ(F2)] = 0.037
wR(F2) = 0.087
S = 1.00
4944 reflections
360 parameters
H atoms treated by a mixture of
independent and constrained
refinement
ꢁ3
˚
Áꢅmax = 0.68 e A
ꢁ3
˚
Áꢅmin = ꢁ0.23 e A
Figure 2
A view of the two-dimensional supramolecular structure of (I)
constructed by two types of aromatic interactions: ꢀ–ꢀ interactions
between quinoline ring systems of L ligands [N2/C4–C12 at (x, y, z) and
(ꢁx, ꢁy + 1, ꢁz + 1)] and C—Hꢀ ꢀ ꢀꢀ interactions between atom C23 of
the 1,2-bdc ligand and a pyridine ring of the L ligand [N2/C6–C10 at (ꢁx,
Table 1
Selected geometric parameters (A, ) for (I).
ꢂ
˚
1
2
3
2
y ꢁ , ꢁz + )].
Cd1—N1
Cd1—N2
Cd1—O1
Cd1—O2
2.295 (3)
2.320 (2)
2.439 (2)
2.484 (2)
Cd1—O1W
Cd1—O4i
Cd1—O3i
2.330 (3)
2.314 (2)
2.481 (2)
It should be pointed out that the related compound [Cd(1,2-
bdc)(H2O)] displays a two-dimensional layer structure, where
neighbouring CdII centres are bridged by carboxylate O atoms
of 1,2-bdc ligands (Wang et al., 2003). Clearly, the L ligand
plays an important role in the formation of the dimeric
structure. It is also noteworthy that the structure of (I) is
different from the related structure [Cd(1,2-bdc)(L0)3]n (L0 =
benzimidazole; Cui et al., 2006). In this compound, the CdII
centre is seven-coordinated by four O atoms from two 1,2-bdc
ligands and three N atoms from three L0 ligands, resulting in a
distorted pentagonal–bipyramidal geometry. The 1,2-bdc
ligands bridge the CdII centres to form an extended helical
chain structure. Neighbouring chains interact through ꢀ–ꢀ
interactions, yielding a two-dimensional structure.
N1—Cd1—O4i
N1—Cd1—N2
O4i—Cd1—N2
N1—Cd1—O1W
O4i—Cd1—O1W
N2—Cd1—O1W
N1—Cd1—O1
O4i—Cd1—O1
N2—Cd1—O1
O1W—Cd1—O1
N1—Cd1—O3i
101.66 (8)
72.53 (9)
136.75 (8)
171.31 (9)
86.69 (9)
99.77 (9)
96.46 (9)
139.74 (8)
82.97 (8)
78.30 (11)
101.57 (9)
O4i—Cd1—O3i
N2—Cd1—O3i
O1W—Cd1—O3i
O1—Cd1—O3i
N1—Cd1—O2
O4i—Cd1—O2
N2—Cd1—O2
O1W—Cd1—O2
O1—Cd1—O2
O3i—Cd1—O2
54.42 (8)
84.12 (8)
81.25 (11)
153.51 (9)
96.92 (9)
89.23 (7)
133.69 (8)
85.48 (9)
52.82 (7)
141.72 (7)
Symmetry code: (i) ꢁx; ꢁy þ 1; ꢁz þ 2.
Table 2
Hydrogen-bond geometry (A, ) for (I).
ꢂ
˚
D—Hꢀ ꢀ ꢀA
D—H
Hꢀ ꢀ ꢀA
Dꢀ ꢀ ꢀA
D—Hꢀ ꢀ ꢀA
N4—H4Aꢀ ꢀ ꢀO1ii
0.86
0.77 (4)
0.83 (4)
1.92
2.11 (4)
1.98 (5)
2.727 (3)
2.815 (4)
2.748 (4)
155
153 (4)
154 (4)
O1W—HW11ꢀ ꢀ ꢀO2i
O1W—HW12ꢀ ꢀ ꢀO4
Experimental
CdCl2ꢀ2.5H2O (0.5 mmol), 1,2-H2bdc (0.5 mmol) and L (0.5 mmol)
were dissolved in distilled water (12 ml), and then triethylamine
(0.01 mol) was added until the pH value of the system was adjusted to
about 5.5. The resulting solution was stirred for about 1 h at room
temperature, sealed in a 23 ml Teflon-lined stainless steel autoclave
and heated at 458 K for 6 d under autogenous pressure. The reaction
system was subsequently cooled slowly to room temperature. Pale-
yellow block-shaped crystals of (I) suitable for single-crystal X-ray
diffraction analysis were collected from the final reaction system by
filtration, washed several times with distilled water and dried in air at
ambient temperature (yield 67%, based on CdII). Compound (II) was
prepared in the same way as (I), using ZnCl2ꢀ2H2O as the metal
source. Pale-yellow crystals were obtained (yield 71%, based on
ZnII).
Symmetry codes: (i) ꢁx; ꢁy þ 1; ꢁz þ 2; (ii) ꢁx; ꢁy þ 1; ꢁz þ 1.
Compound (II)
Crystal data
[Zn2(C8H4O4)2(C19H10ClFN4)2-
(H2O)2]
Mr = 1192.52
ꢁ = 104.655 (5)ꢂ
3
V = 2413.8 (12) A
Z = 2
˚
Monoclinic, P21=c
Mo Kꢂ radiation
ꢃ = 1.19 mmꢁ1
T = 293 K
0.29 ꢄ 0.24 ꢄ 0.22 mm
˚
a = 8.695 (3) A
˚
b = 21.720 (6) A
˚
c = 13.211 (4) A
ꢃ
Acta Cryst. (2009). C65, m459–m462
Wang et al.
[M2(C8H4O4)2(C19H10ClFN4)2(H2O)2] (M = Cd and Zn) m461

metal-organic compounds
˚
0.93 A) and refined as riding, with Uiso(H) values set at 1.2 times
Ueq(carrier).
Data collection
Bruker APEX diffractometer
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
Tmin = 0.703, Tmax = 0.772
13479 measured reflections
4772 independent reflections
3026 reflections with I > 2ꢄ(I)
Rint = 0.044
For both compounds, data collection: SMART (Bruker, 1997); cell
refinement: SAINT (Bruker, 1999); data reduction: SAINT;
program(s) used to solve structure: SHELXS97 (Sheldrick, 2008);
program(s) used to refine structure: SHELXL97 (Sheldrick, 2008);
molecular graphics: SHELXTL-Plus (Sheldrick, 2008); software used
to prepare material for publication: SHELXL97.
Refinement
R[F2 > 2ꢄ(F2)] = 0.050
wR(F2) = 0.116
S = 1.01
4772 reflections
360 parameters
H atoms treated by a mixture of
independent and constrained
refinement
ꢁ3
˚
Áꢅmax = 0.40 e A
The authors thank Jilin Normal University for generously
supporting this study.
ꢁ3
˚
Áꢅmin = ꢁ0.43 e A
Table 3
Selected geometric parameters (A, ) for (II).
Supplementary data for this paper are available from the IUCr electronic
archives (Reference: SK3340). Services for accessing these data are
described at the back of the journal.
ꢂ
˚
Zn1—O1
Zn1—O2
Zn1—O1W
2.364 (4)
2.377 (3)
2.135 (3)
Zn1—O4i
Zn1—N1
Zn1—N2
2.094 (2)
2.092 (3)
2.105 (3)
References
Bruker (1997). SMART. Version 5.622. Bruker AXS Inc., Madison, Wisconsin,
USA.
Bruker (1999). SAINT. Version 6.02. Bruker AXS Inc., Madison, Wisconsin,
USA.
Chen, Z.-F., Zhang, Z.-L., Tan, Y.-H., Tang, Y.-Z., Fun, H.-K., Zhou, Z.-Y.,
Abrahams, B. F. & Liang, H. (2008). CrystEngComm, 10, 217–231.
Cui, Y.-C., Wang, J.-J., Che, G.-B. & Li, C.-B. (2006). Acta Cryst. E62, m2761–
m2763.
N1—Zn1—O4i
N1—Zn1—N2
O4i—Zn1—N2
N1—Zn1—O1W
O4i—Zn1—O1W
N2—Zn1—O1W
N1—Zn1—O1
O4i—Zn1—O1
96.55 (10)
79.08 (11)
132.58 (10)
174.69 (11)
88.76 (11)
97.48 (11)
93.95 (11)
143.48 (9)
N2—Zn1—O1
O1W—Zn1—O1
N1—Zn1—O2
O4i—Zn1—O2
N2—Zn1—O2
O1W—Zn1—O2
O1—Zn1—O2
83.76 (10)
81.60 (12)
91.86 (11)
90.61 (10)
136.36 (10)
87.88 (11)
54.10 (9)
Eddaoudi, M., Moler, D. B., Li, H., Chen, B., Reineke, T. M., O’Keeffe, M. &
Yaghi, O. M. (2001). Acc. Chem. Res. 34, 319–330.
Hagrman, P. J., Hagrman, D. & Zubieta, J. (1999). Angew. Chem. Int. Ed. 38,
2638–2684.
Symmetry code: (i) ꢁx; ꢁy þ 1; ꢁz þ 2.
Ockwig, N. W., Delgado-Friedrichs, O., O’Keeffe, M. & Yaghi, O. M. (2005).
Acc. Chem. Res. 38, 176–182.
Qiao, Q., Wu, G.-Q., Tang, T.-D. & Ng, S. W. (2009). Acta Cryst. C65, m146–
m148.
Qiao, Q., Zhao, Y.-J. & Tang, T.-D. (2008). Acta Cryst. C64, m336–m338.
Table 4
Hydrogen-bond geometry (A, ) for (II).
ꢂ
˚
D—Hꢀ ꢀ ꢀA
D—H
Hꢀ ꢀ ꢀA
Dꢀ ꢀ ꢀA
D—Hꢀ ꢀ ꢀA
¨
Sheldrick, G. M. (1996). SADABS. University of Gottingen, Germany.
N4—H4Aꢀ ꢀ ꢀO1ii
0.86
0.83 (4)
0.89 (4)
1.95
2.06 (4)
1.93 (4)
2.738 (4)
2.807 (4)
2.753 (4)
152
150 (4)
153 (4)
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.
Wang, S., Hou, Y., Wang, E., Li, Y., Xu, L., Peng, J., Liu, S. & Hu, C. (2003).
New J. Chem. 27, 1144–1147.
O1W—HW11ꢀ ꢀ ꢀO2i
O1W—HW12ꢀ ꢀ ꢀO4
Wang, X.-L., Bi, Y.-F., Lin, H.-Y. & Liu, G.-C. (2007). Cryst. Growth Des. 7,
1086–1091.
Symmetry codes: (i) ꢁx; ꢁy þ 1; ꢁz þ 2; (ii) ꢁx; ꢁy þ 1; ꢁz þ 1.
Wang, X.-Y., Wang, J.-J. & Ng, S. W. (2008). Acta Cryst. C64, m401–m404.
Yang, J., Li, G.-D., Cao, J.-J., Yue, Q., Li, G.-H. & Chen, J.-S. (2007). Chem. Eur.
J. 13, 3248–3261.
Yang, J., Ma, J.-F., Liu, Y.-Y., Ma, J.-C. & Batten, S. R. (2009). Cryst. Growth
Des. 9, 1894–1911.
For both compounds, the water H atoms were located in a
difference Fourier map and thereafter refined freely. All other H
˚
atoms were positioned geometrically (N—H = 0.86 A and C—H =
ꢃ
m462 Wang et al. [M2(C8H4O4)2(C19H10ClFN4)2(H2O)2] (M = Cd and Zn)
Acta Cryst. (2009). C65, m459–m462