| In recent years, the coordination polymers have attracted comprehensive attention because of their intriguing architectures as well as their tremendous potential applications for gas storage, chemical separations, catalysis, nonlinear optics, and so on. Meanwhile, functionalization and modification of the ligands to construct new metal-organic frameworks are fascinating and significant work in the crystal engineering. Studies have indicated that the type of the organic ligand and the coordination geometry of metal ion have crucial influence on the structure and the property of the coordination polymer, and other factors such as the ratio of materials, temperature, and pH play synergetic effects. The aromatic carboxylic acid containsπ-electron system which is more conducive to electronic transmission. In addition, rich coordination modes of the carboxylic acid group can easily build new structures of complexes. The 1,4- and 1,3-benzenedicarboxylic acid (BDC) have been widely utilized to construct coordination polymers, however, the introduction of big substituent on phenyl ring to build new complexes are rarely report. In this paper, we have used four kinds of modified aromatic carboxylic acid (1,4-BDC, 1,3-BDC, etc.) as main ligands with transition metal ions to build novel coordination polymers. The study on synthetic conditions and role for these new complexes are also carried out.Nine novel complexes have synthesized by self-assembly under hydrothermal and conventional method. The crystal structures have been characterized by elemental analysis, IR spectra, and determined by single crystal X-ray diffraction analysis. The thermogravimetric analysis, fluorescence properties as well as the magnetic properties of them are also discussed. The experiment results as follows:1. Two novel complexes have been synthesized by modified 1,4-BDC (H2L1 = 2,5-dibenzoylterephthalic acid) as main ligands with CoII ions under hydrothermal method, namely, {[Co2(L1)1.5(OH)(H2O)2]·2H2O} (1) and [CoL1(bpp)] (2) (bpp = 1,3-bis(4-pyridyl)propane). 1 exhibits a 3D framework assembled from tetra-nuclear cobalt-oxygen clusters bridged by carboxylic O atoms with a (412·63) topology; 2 exhibits a 2D layered structure. The magnetic properties of them are discussed, the result shows that there presence of antiferromagnetic interactions in 1 and 2.2. Five novel complexes based on modified 1,3-BDC (H2L2 = 2,4-dibenzoylisophthalic acid; H2L3 = 4,6-bis(4-methylbenzoyl)isophthalic acid) have been constructed by using containing nitrogen ligands as the second ligand with NiII, CoII ions under hydrothermal and conventional methods. Namely, [Ni2(L2)2(bpp)2(μ2-H2O)] (3), [Ni(L2)(4,4′-bpy)(H2O)] (4) [Co2(L2)2(2,2′-bpy)2(H2O)2] (5), {[Co(L3)(4,4′-bpy)(H2O)2]·3H2O} (6) and [Co(L3)(4,4′-bpy)] (7) (4,4′-bpy = 4,4′-bipyridine, 2,2′-bpy = 2,2′-bipyridine). 3 possesses 3D network with (36·48·57) topology, which is constructed by two kinds of helical chains; 4,6 and 7 are both 2D layer structures; 5 is zero dimensional single molecule structure. The thermogravimetric are characterized for 3, 6, and 7. Moreover, the magnetic properties of complex 3 are also studied, the result shows that the ferromagnetic interactions among NiII ions.3. Two coordination polymers [Co(BYBA)2(4,4′-bpy)(H2O)2]·H2O (8) and [Zn(BYBA)2(4,4′-bpy)] (9), have been prepared under hydrothermal method base on 2-benzoylbenzoic acid (BYBAH), 4,4′-bpy, CoII, and ZnII ions. 8 exhibits 1D polymeric chains; 9 is composed by 1D zigzag chains. The fluorescent properties of complexes 8 and 9 have been also investigated in solid state, which exhibit a blue-shift compared with free BYBAH.
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