Synthesis Of Benzimidazoles And Thiosemicarbazone And The Ions Recognition Properties

This paper includes four chapters:Chapter1:The first chapter is about the research of benzimidazoles and cation recognition in recent years, which contain the following part:(i) the research status and the significance of the Synthesis of benzimidazoles and cations recognition;(ii) A brief review for the new research of benzimidazoles.(iii) the latest research status of anions and ions recognition properties about complex of benzimidazoles.Chapter2:Synthesis of benzimidazole compounds by the reaction of o-phenylenediamine phosphate with fatty acids under solvent-free conditions has been studied. The reaction conditions were optimized by single-factor and orthogonal experiment. Under the optimal reaction conditions amplification experiment was realized and the yield was89.3%, which under the reaction conditions at reflux temperature for7h with o-phenylenediamine of50mmol, n(o-phenylenediamine):n(formic acid) of1.0:1.5and phosphate4g. The process is superior to the traditional solvent-free synthesis and microwave solvent-free synthesis. The process is simple, high yield, without solvent, corrosion of equipment of low, environmental friendly, can be mass-produced in the laboratory and with the potential to be a large number of industrial production.The third chapter is about two new N-aryl coumarin methyl ketone thiosemicarbazone receptors were designed and synthesized. The binding properties of the receptors with cations such as Fe3+, Hg2+, Ag+, Ca2+, Cu2+, Zn2+, Pb2+, Cd2+, Ni2+, Cr3+and Mg2+in DMSO were investigated by UV-vis spectroscopy. The results showed that the two receptors had a better selectivity for Cu2+, and exhibited no evident binding with others cations. The UV-vis data indicated that1:1stoichiometry complex was formed between the receptors and Cu2+. The sensing of Cu2+by this sensor was found to be reversible, with the Cu2+-induced color being lost upon addition of EDTA. The process of titrating sensor of S2with Cu2+is reversible, and that S2could therefore be used as an off-on switch chemosensor. Furthermore, the anion binding interaction of receptor-anion was also studied using MS which proved that the nature of the interaction between the subject and object.The fourth chapter is about a novel and sensitive anion receptor S4, had been designed and synthesized. Host S4behaves a single selectivity and sensitivity in the recognition for CN- anion over other anions such as F-, Cl-, Br-, I-, H2PO4-, HSO4-ClO4-and CN-by naked-eyes and UV-vis spectra changes and fluorescence spectrum changes in aqueous solution (8.5:1.5v/v).