Studies On Optical And Electrochemical Properties Of Aromatic Heterocyclic Compounds, Synthesis And Catalytic Performance Of Metal Coordination Complexes

Firstly, salicylaldehyde (SAH) was studied by traditional electrochemicalmethod and spectroelectrochemical method, and it has been reported in thispaper that rich information on kinetics and the oxidation mechanism of SAH.The results show that SAH was initially oxidized to phenoxyl radicals, followedby a series of electrochemical steps leading to different final products indifferent pH media. Under alkaline conditions, the main product of oxidationwas polysalicylate deposited on the electrode surface. And in acidic media, theproducts of oxidation were3-formyl-o-benzoquinone and p-benzoquinone.Secondly, the interaction of umbelliferone (UMB) with tryptophan (Trp),tyrosine (Tyr) and phenylalanine (Phe) were studied in Tris-HCl buffer solutionat pH7.4via fluorescence spectroscopy and ultraviolet spectroscopy. Theresults show that UMB can strongly quench the fluorescence of the threearomatic amino acids with the maximum quenching wavelengths at347,273and256nm, respectively. Data analyses based on the Stern-Volmer curve and theUV spectroscopy show that static quenching occurred through the formation ofthe complexes of UMB with each aromatic amino acid in a molar ratio of1:1and abtained the binding constant Kcwere above103. Hydrogen bond andvander Waals force may play a major role in the reaction of UMB with Trp,whereas hydrophobic interaction should be responsible for the binding of UMBwith Tyr and Phe. In addition, the dipole-dipole interaction may be anotherfactor in the reactions between UMB and the three amino acids.Finally, three coordination complexes have been synthesized by hydrothermalmethods using transition metal salt and three aromatic heterocyclic ligands,which were characterized by infrared spectra, X-ray powder and single crystaldiffraction. The results show that1is a Zn complex with one-dimensionalstructure,2is a Mn complex with three-dimensional structure, and both of themare the new coordination complexes based on3,5-pyrazole dicarboxylate and1,10-phenanthroline.3is a simple Co complex based onimidazole-4-carboxylate. And3had been used as catalyst integrated with H2O2at over90%efficiency for the catalytic degradation of methyl orange dye,methylene blue and rhodamine, which can be a potential efficientenvironmentally catalyst for degradation of organic dyes.