Ferrocene Iminodiacetic Acid Functional Complexes Synthesis, Crystal Structure And Performance

The ferrocenyl amino-acid complexes have the special chemical, stereochemical, and electrochemical properties due to having the ferrocenyl group and the amino-acid group, so chemists have an strongly interested in introducing the ferrocenyl group to the amino-acid group. The rational design and synthesis of the ferrocenyl amino-acid coordination compounds, and researching the properties and applications of them have received much attention. The complexes would have some potential applications in functional materials, genetic engineering and biology.We obtained three single crystals by the reactions of ferrocenyl methyl iminodiaceticnate (FcCH₂N(CH₂COONa)₂, L) and corresponding metal ions, and conformed the crystal structures of the three complexes by single crystal X-ray diffraction. Then we characterized the compounds by IR and elementary analysis. In addition, we studied the electrochemical properties, fluorescent properties and polyphenol oxidation reactivity.Firstly, the complex [CoL(H₂O)₃] (1) was synthesized at room temperature, and characterized by single crystal X-ray diffraction. In the crystal structure, the coordination geometry of Co(II) ion is a distorted octahedron, the coordination model of the ferrocenyl methyl iminodiacetic acid is tridentate chelated fashion. Each structural unit interacts with adjacent structural unit by hydrogen bonds, leading to two-dimensional supramolecular motif.Secondly, we synthesized the dimer [PbL(H₂O)]₂ (2) at room temperature. In the crystal structure, the ferrocenyl methyl iminodiacetic acid not only coordinated by tridentate chelated fashion, but also joint the other Pb(II) through one oxygen atom which join the chelate coordination. We also found the weak Pb…Pb interactions in this coordination compound.Finally, we use L to react with NiCl₂·6H₂O and obtain two-dimensional coordination polymer [NiL(CH₃OH)·(CH₃OH)₃]_n (3). In the crystal structure, there are two kinds of Ni(II) ions that located in the different coordination enviroment. The ferrocenyl methyl iminodiacetic acid not only coordinated with one kind of Ni(II) ions by tridentate chelated fashion, but also joint the other kinds of Ni(II) ions through oxygen atom which don't join the chelate coordination. All the Ni(II) ions locate in the same plane; the mean deviation from plane is 0.0000 A.The electrochemical properties of ferrocenyl methyl iminodiaceticnate and three complexes have been investigated in the solution state. The results shown that the oxidation-reduction reversibility of ferrocenyl methyl iminodiaceticnate is better than that of three complexes, and the half-wave redox potentials of three complexes were all slightly higher than that of ferrocenyl methyl iminodiaceticnate. The fluorescent properties of ferrocenyl methyl iminodiaceticnate and three complexes have been observed in the solid state at room temperature. The emission spectrums of three complexes are similar to ferrocenyl methyl iminodiaceticnate's. The fluorescent intensities of three complexes are stronger than ferrocenyl methyl iminodiaceticnate's.In addition, we studied the polyphenol oxidation reactivity of three complexes in heterogeneous system. The results indicated that the polyphenol oxidation reactivity of three complexes is better.