Synthesis And Spectral Studies Of Triphenyl Amines Fluorescent Probes

Chapter 1:Triphenyl amines possess excellent optical properties. The fluorescent probe with triphenylamine has many advantages, such as, strong UV absorption, adjustable fluorescence emission properties and the wavelength of the radiation at visible-light region. This chapter reviewed progress and application of fluorescent probes which with triphenylamine as fluorophore or with Schiff bases as recognition group.Chapter 2:The new Schiff base compound 2-(4-(diphenylamine) benzylidene) thiosemicarbazide was obtained through the condensation reaction of 4-diphenylamine benzaldehyde and thiosemicarbazide. The structure of 2-(4-(diphenylamine) benzylidene) thiosemicarbazide was characterized by’HNMR. The spectral characteristics of 2-(4-(diphenylamine) benzylidene) thiosemicarbazide and the interaction with different metal ions were studied by UV and fluorescence spectroscopy. In addition, the effects of solvent, concentration, pH values were investigated and the best experimental conditions were got. The results showed that 2-(4-(diphenylamine) benzylidene) thiosemicarbazide can recognize Hg2+ with little interference under acidic and neutral conditions, but with obvious interference of Cu2+ in alkaline conditions.2-(4-(diphenylamine) benzylidene) thiosemicarbazide and Hg2+ could form a complex with 2:1. The linear range was 9.5xl0-8-1.14xl0-6 mol/L and the detection limit was 1.5 × 10-9 mol/L. This method has many advantages, simple synthesis, good selectivity and high sensitivity, and has potential applications in the environment detection of trace Hg2+Chapter 3:Based on the second chapter,2-(4-(diphenylamine) benzylidene) thiosemicarbazide can interaction with Cu2+ and Hg2+ at the same time under alkaline conditions. Masking Hg2+ with NaBH4, the interaction of the compound to Cu2+ was researched by UV and fluorescence spectroscopy. The results show that they formed 1:1 complex with the binding constant of 4 × 104 M"1, a good linear relationship in 0.45-3.6xlO-6 mol/L and the detection limit of 1.7xlO-7 mol/L. The method of Cu2+ detection in methanol-water system was achieved. Combined with the chapter two,2-(4-(diphenylamine) benzylidene) thiosemicarbazide could detect Hg2+ and Cu2+ under different pH conditions, respectively.Chapter 4:The new Schiff base fluorescent probe, N’-benzylidene-4-(diphenylamine) benzoyl hydrazine, was synthesized through reduction, esterification, amination and condensation and its structure was characterized by 1HNMR. The spectral characteristics of the compound and the interaction with different metal ions were researched by UV and fluorescence spectroscopy. In addition, the effects of solvent, concentration, pH were investigated and the best experimental conditions were got. The results showed that N’-benzylidene-4-(diphenylamine) benzoyl hydrazine could recognize Fe+ with small interference of other metal ions, such as, Hg+, Cu2+, Cr3+, Fe2+. The fluorescence method of Fe3+ detection in methanol-water system was established, which had the linear range of 2.5×10-5-1.0×l0-3mol/L and the detection limit of 1.5×10-5 mol/LChapter 5:The spectra of triphenyl amine compound 5-methyl-2-(p-N, N-diphenylaminophenyl)-4-acetyl oxazole was studied in detail By UV and fluorescence spectroscopy, which compared with the other three spectra of compounds containing benzene and oxazole. The results showed that due to triphenyl amine had the ability of good electron donating, molecules possessed a significant intramolecular charge transfer characteristics that make it with fullerene C6o form intermolecular charge transfer complexes.