metal-organic compounds
II
As shown in Fig. 1, each Cd ion of (I) has a pentagonal–
Acta Crystallographica Section C
Crystal Structure
Communications
bipyramidal coordination, with five O atoms from three 1,4-
PDA ligands occupying the equatorial sites and two N atoms
from two bpp ligands located on the axial positions. The Cd—
ISSN 0108-2701
˚
O bond lengths range from 2.313 (3) to 2.488 (3) A, and the
˚
Cd—N distances are 2.340 (3) and 2.315 (3) A. Two equivalent
Poly[[l -1,3-bis(pyridin-4-yl)propane]-
II
Cd ions related by an inversion centre with an interatomic
2
˚
distance of 3.7959 (9) A are bridged by a single carboxylate O
(l3-1,4-phenylenediacetato)cadmium]
atom from each of two 1,4-PDA ligands to form a [Cd (1,4-
2
PDA) ] unit. Adjacent [Cd (1,4-PDA) ] units are linked via a
2
2
2
Dong Liu
double bridge involving coordination at both ends of two 1,4-
PDA ligands to afford a one-dimensional [Cd (1,4-PDA) ]
2
2 n
College of Chemistry and Materials Science, Huaibei Normal University, Huaibei
chain (Fig. 2). These chains are crosslinked through bridging
bpp ligands to generate a rare two-dimensional 6-connected
net. The size of each triangular grid in the two-dimensional net
2
35000, Anhui, People’s Republic of China
Received 6 October 2011
Accepted 23 December 2011
Online 10 January 2012
˚
is 10.31 ꢀ 12.29 ꢀ 12.29 A (Fig. 3).Different from that of
the reported complex {[Cu (1,4-PDA) (OH) (bpp) ]2H O}
2
4
3
2
2
n
(Sposato et al., 2010) constructed from trans-1,4-PDA and
anti–anti bpp ligands, the conformations of the 1,4-PDA and
bpp ligands in (I) are cis–gauche and anti–gauche, respectively.
Solvothermal reaction between Cd(NO ) , 1,4-phenylene-
3
2
diacetate (1,4-PDA) and 1,3-bis(pyridin-4-yl)propane (bpp)
afforded the title complex, [Cd(C H O )(C H N )] . Adja-
10
8
4
13 14
2 n
II
cent carboxylate-bridged Cd ions are related by an inversion
centre. The 1,4-PDA ligands adopt a cis conformation and
II
connect the Cd ions to form a one-dimensional chain
extending along the c axis. These chains are in turn linked
into a two-dimensional network through bpp bridges. The bpp
ligands adopt an anti–gauche conformation. From a topologi-
cal point of view, each bpp ligand and each pair of 1,4-PDA
II
ligands can be considered as linkers, while the dinuclear Cd
unit can be regarded as a 6-connecting node. Thus, the
structure can be simplified to a two-dimensional 6-connected
network.
Comment
The design and construction of coordination polymers based
on transition metals and organic spacers are currently
attracting considerable attention (Moulton & Zaworotko,
The aromatic rings of the organic ligands of (I) are not close
to one another. The closest ring–ring contact is between the
2001; Kitagawa et al., 2004). Flexible ligands such as 1,4-
i
N1/C1–C5 and N2 /C9 –C13 rings [symmetry code: (i) x,
i
i
phenylenediacetate (1,4-PDA) and 1,3-bis(pyridin-4-yl)pro-
pane (bpp) are usually the typical building elements in coor-
dination networks, since they can adopt varied coordination
modes and geometries. For 1,4-PDA, the two carboxylate
groups can exhibit various coordination modes. Furthermore,
this flexible ligand can adopt either cis or trans conformations
3
1
˚
ꢁ
y + , z ꢁ ], at a distance of 3.944 (3) A.
2
2
(Blake et al., 2010; Lan et al., 2011; Sposato et al., 2010; Yang et
al., 2010). The bpp ligand is more flexible than 1,4-PDA due to
its propyl group, and it can adopt anti–anti, anti–gauche or
gauche–gauche conformations (Carlucci et al., 2000; Hulvey et
al., 2010; Mao et al., 1999). To understand further the coor-
dination chemistry of flexible dicarboxylate and dipyridyl
II
Figure 1
ligands, we employed these two ligands in a reaction with Cd
II
The coordination environment of the Cd ion in (I), showing the atom-
numbering scheme. Displacement ellipsoids are drawn at the 30%
probability level. [Symmetry codes: (i) x, y, z ꢁ 1; (ii) ꢁx + 1, ꢁy + 1, ꢁz;
ions under solvothermal conditions and obtained the title two-
dimensional coordination polymer, [Cd(C H O )(C H -
N )] , (I).
10
8
4
13 14
1
2
1
2
(iii) ꢁx + 1, y ꢁ , ꢁz ꢁ .]
2
n
m34 # 2012 International Union of Crystallography
doi:10.1107/S0108270111055454
Acta Cryst. (2012). C68, m34–m36