Design And Synthesis Of S-Triazine Derivations For Metal Ion Recognition

In recent years, photochemical sensor has been widely applied in the detection of metal ions and anions of simples or environment due to the high sensitivity and selectivity, short time-consuming, and many other advantages. It also demonstrated the pratical application value in environmental science, chemistry, medical science, bioscience and other fields. In this paper, several photochemical probes were designed and synthesized using triazine as starting materials. The method of quantitative analysis was established utilizing optical properties of photochemical sensor, and we also studied their interactions, combination mode and mechanism. The main contents are divided into four chapters as follows.In chapter1, the tendency of fluorescent and colorimetric probes was mainly described, which reports at home and abroad in recent five years. Meanwhile the main application area of triazine compounds was also summarized in this chapter.In chapter2, two compounds of s-triazine derivatives which named2,4-Dimethyl-6-[2-(4-N,N-dimethylamino)phenylethenyl]-1,3,5-s-triazine (Al) and2-styryl-4,6-dimethyl-1,3,5-triazine (A2) were synthesized and characterized by1H NMR, Mass and elemental analysis. The interactions and combine model between the metal ions and host compounds were investigated by UV-vis and NMR spectroscopy. Results indicated that the absorption spectrum of compound A1had a remarkable change when it combined with Fe3+and Cu2+, and the maximum absorptive peaks shifts from393nm to525nm and513nm, respectively. The models of compound Al intergraded with Fe3+and Cu2+were1:1and2:1, and with the same remarkable color change from yellow to pink by naked-eye colorimetric detection. The association constants of A1-Fe3+and Al-Cu2+were1.8×104L mol"1and2.6×1010L mol-1respectively. Meanwhile, the spectrum of compound A2underwent to distinct changed when it intergraded with Fe3+and the maximum absorptive peak shifted from304nm to357nm. But less change was observed when it intergraded with Cu2+. The ratio of compound A2intergraded with Fe3+was1:1and the association constants was1.0×105L mol-1. Therefore, we could concluded that Fe3+intergraded with the ring of triazine of the compounds A1and A2, but the Cu2+intergraded with N atom of the methylamino of the compound Al. At the same time, the interactions of compounds A1and A2with other ions such as Li+, K+, Mg2+, Ca2+, Co3+, Ni2+, Ag+, Cd2+, Hg2+and Zn2+were also investigated, but obvious absorption spectral changes was not observed.In chapter3, we designed and synthesized four compounds of s-triazine derivatives which named2,4-di(2-thiophene)-6-[2-(4’-N,N-dimethylamino) phenylethenyl]-1,3,5-s-triazine (A3),2,4-(2-thiophene)-6-(phenylethenyl)-1,3,5-s-triazine(A4),2,4-(2-furan)-6-[2-(4’-N,N-dimethylamino) phenylethenyl]-1,3,5-s-triazine (A5) and2,4-(2-furan)-6-(phenylethenyl)-1,3,5-s-triazine (A6), respectively. They were also characterized by H NMR, Mass and elemental analysis. We studied the interactions between the metal ions and host compounds (A3, A4, A5and A6) by UV-vis and1H NMR spectroscopy. The compound A3、A5exhibited sensing towards Cu2+, Hg2+and Fe3+but weakly sensing toward other cations, such as Li+, Na+, K+, Mg2+, Ca2+, Zn2+, Ni2+, Ag+, Cd2+and Co3+. Meanwhile, the color of the solution changed from yellow to red. The ratios of compound A3、A5intergrated with Cu2+, Hg2+and Fe3+were1:1. The addition of Cu2+, Hg2+and Fe3+could also induce the absorption spectrum changes of compounds A4, A6, but the color change was not obviously.In chapter4,2,4-(2-pyridine)-6-[2-(4-N,N-dimethylamino) phenylethenyl]-1,3,5-s-triazine (A7) and2,4-(2-pyridine)-6-(phenylethenyl)-l,3,5-s-triazine (A8) were prepared. They were characterized by1H NMR, Mass and elemental analysis and studied the interactions between the metal ions by UV-vis and1H NMR spectroscopy. The chemsensor A7exhibited selective absorbance enhancement to Cu2+at530nm over other metal ions, such as Li+, K+, Mg2+, Ca2+, Fe3+, Co3+, Ni2+, Ag+, Cd2+, Hg2+and Zn2+. Upon Cu2+addition, the color of A7solution changed from yellow to amaranth. A1:1metal-ligand complex between copper ion and compound A7was formed, and its binding constant was estimated as K=4.4×108L mol-1.