| In this paper, we use carboxylate acid, such as, terephthalic acid and 1,3,5-benz- enetricarboxylate; N-heterocyclic dicarboxylate, for example, pyridine-2,6-dicarboxylic acid; benzimidazole derivant, for instance, benzimidazole-2-carboxylic acid, and N-containing auxiliary bridging ligand, such as, 4,4′-azpy to construct series of novel metal-organic coordination polymers with transition metal ion by intermolecular self-assembly under solvothermal conditions. The strutures and some properties of these compounds have been characterized.Polydentate ligand pyridine-2,6-dicarboxylic acid and N-containing bridging ligand 4,4′-azpy are selected to construct the 1D metal-organic coordination polymer Zn[(pda)(azpy)]·4H2O (1) by intermolecular self-assembly. In this compound, 4,4′-azpy acts as the main bridging ligand to construct the 1D liner. Between chains, Van der Waals force,π-πstacking and water clusters interations contribute to the formation of a three-dimentional supramolecular network.Terephthalic acid is selected as the bridging ligand to construct the 2D non-interpenetrate sheets with 63 topology (C2H8N)2[Zn2(C8H4O4)3(C2H7N)2]·2C3H7- NO·6H2O (2) which are stacked together in an…ABAB…packing mode along the c axis by intermolecular self-assembly. The distance between adjacent A and B sheets is ca 7.3 ? (Zn…Zn). The offset distance between the adjacent sheets is ca 12.3 ? along the a axis in the ab plane. In the structure, weak N-H…O and O-H…O hydrogen bonds are observed.The two-dimensional 36 network structure of [Mn3(bdc)3(DMA)4]·0.5H2O (3) in which terephthalic acid acts as the bridging ligand is constructed from the M3(O2CR)6 secondary building unite (SBU). It is very interesting that because of two different central metal atoms and two different terminal metal atoms, there are two types of Mn3(O2CR)6 SBUs in the structure (3). Two types of 1D chains constructed from two different M3(O2CR)6 trimetallic building units are linked together through BDC ligands to form the 2D layer. Hydrogen bonds are involved in the linking of adjacent sheets to construct the 3D structure.Transition metal ion Co2+ is selected as a connector, benzimidazole-2-carboxylic acid as a bridging ligand to synthesize the porous zeolitic imidazolate frameworks (ZIFs) Co(C7H5N2)2·1.5H2O (4) which has 3D cages by intermolecular self-assembly. The cage which includes 24 vertices and 36 benzimidazole links is a dodecahedron which has four rectangles and eight hexagonals. The radius of the largest sphere that will fit into the cavity is 7.8 ? and the Co···Co distance is≈6.017 ?. A Co atom is coordinated to four benzimidazoles to create a corresponding tetrahedron. The tetrahedrons are linked by corner-sharing into 3D zolitic framworks.1,3,5-benzenetricarboxylate and transition metal ion Zn2+ are selected to construct the 3D porous coordination polymer [NH2(CH3)2]Zn(BTC)·DMA (5) by intermolecular self-assembly. The structure is constructed from triangular and distorted octahedral building blocks, the framework of which can be described as a non-interpenetrated decorated rutile net. The specifically shaped dimeric zinc carboxylate SBU is expected to be a useful building motif for the design and synthesis of porous MOFs with a specific topology.These complexes (1-5) were characterized by elemental analysis, IR spectrum, thermogravimetric analysis, single crystal X-ray diffaration and powder X-ray diffraction.
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