Syntheses, Structures And Properties Of Functional Coordination Compounds Based On Naphthylacetic Acids And Nitrogen-Containing Heterocyclic Ligands

The metal-organic complxes have received much attention in the field of coordi nation chemistry because of their unique performance in luminescence, magnetism, c atalysis, adsorption and separation et al. Selection of suitable organic ligands is usu ally crucial for the formation of the novel coordination compounds in the supramol ecular chemistry and crystal engineering. The organic carboxylic acid and N-containi ng heterocyclic ligands are of current interest for chemists due to their excellent co ordinating ability and variable coordination fashions. By utilizing α/β-naphthylacetic acid and several N-containing imidazole ligands to react with different transition me tal ions, twenty five new complexes, formulated as, [Mn(α-NAA)2(H20)2] (1), [Cu(α-NAA)2] (2), [Zn(a-NAA)2(H2O)2] (3), [Cu4(α-NAA)8(CH3CN)2] (4), [Cu(2-Etlm)2(α-NAA)2] (5), [Ni(2-Etlm)2(a-NAA)2] (6), [Cd(2-Etlm)2(a-NAA)2] (7), [Ni(2-Prlm)2(a-N AA)2] (8), [Co(2-Prlm)2(a-NAA)2] (9), [Cd(2-Prlm)2(α-NAA)2] (10), [Cu(bim)(a-NA A)2-H2O] (11), [Cu2(bim)4(α-NAA)4-2H2O] (12), [Mn(bim)2(a-NAA)2-H2O] (13), [Ni(b im)2(a-NAA)2-H2O] (14), [Co(bim)2(α-NAA)2·H2O] (15), [Cu(DMB)2(α-NAA)2]2 (16), [Co(DMB)2(a-NAA)2] (17), [Ni(DMB)2(α-NAA)] (18), [Zn(DMB)2(α-NAA)Cl] (19), [Cd(DMB)2(a-NAA)2] (20), [Co(bbbm)(α-NAA)2] (21), [Co(bbdmbm)(α-NAA)2] (22), [Ni(bbmb)(a-NAA)2] (23), [Ni(bbix)(β-NAA)2] (24) and [Ni(bbix)(β-NAA)2] (25). (a-HNAA= a-naphthylacetic acid, β-HNAA= β-naphthylacetic acid,2-Ethn= 2-eth ylimidazole,2-Prlm=2-propylimidazole,bim=benzimidazole, DMB= 5,6-dimethylbenzi midazole, bbbm= 1,4-bis(benzimidazol)butane, bbdmbm=1,4-bis(5,6-dimethylbenzi midazol)butane, bbix=1,4-bis(benzimidazol-1-ylmethyl)benzene), bbmb=1,4-bis(2-meth ylbenzimidazol)butane were synthesized with novel structures.The coordination compounds were characterized by elemental analyses, IR spectra, XRD, X-ray single crystal diffraction. In addition, the thermal stabilities, electrochemical, fluorescent and magnetic properties of the complexes were also presented.Complex 2 exhibits a 1D chain and crystallizes in the orthorhombic space group Pbcn. Each Cu(Ⅱ) ion is connected to five oxygen atoms from five NAA anions to give a distorted square pyramidal geometry. Further, the complex shows strong anti ferromagnetic property.Complex 11 can change from yellow to grass green when heating to 50℃. As the sample was placed at room temperature, and then which can be turned into yellow again, which indicates that complex 11 has the property of thermo chromic. The reasons of the thermo chromic also have been studied by thermo gravimetric data.Complexes 16 and 17 show high catalytic activities on the degradation of Congo red. The reaction is a first-order kinetic process. The degradation efficiency of Congo red can reached to 96.9% for complex 16 after eighty minutes, which can be used as a potential catalytic material.Fluorescence spectra show that the complexes 9,10,13,15,21,23 and 25 exhibit strong fluorescence properties in solid state at the room temperature, which reveal their potential application as luminescent materials.Thermo gravimetric analyses indicate that all complexes show high thermal stabilities.