Synthesis And Properties Of Novel Schiff Base Compounds And Their Complexes With Europium And Terbium

In recent years， acylhydrazone compounds has been paid much attention in the ifelds ofchelating agent and analytical reagent because of the well coordination of theazomethine(C=N) and carbonyl(C=0) groups in their structures, and it is tremendouslysigniifcant to carry out the research and application development of acylhydrazonecompounds. In this paper, two series of novel acylhydrazone Schiff bases have beensynthesized, and characteirzed by NMR, mass spectrometry, inrfared spectra and elementalanalysis. Their corresponding complexes with Europium or Terbium ion have also been prepared, andcharacteirzed by elemental analysis, EDTA titrimetric analysis, IR and UV spectra as well as molarconductivity measurements. The luminescent and electrochemical properties of the titlecomplexes were respectively investigated by luminescent spectra and cyclic voltammetry. Therelationships between the structure of the title compouds and the properties of their complexeswere also been discussed. The main research works are as follows:(1)With menthyl salicylate and aniline derivatives as starting material, a series ofsalicylaldehyde salicylhydrazone derivatives with acetanilide as the end group wassynthesized by the reaction of hydrazinolysis and condensation successively. Theircorresponding complexes with Europium or Terbium ion have also been prepared. Theluminescent properties of the title complexes were investigated by luminescent spectra, andthe lfuorescent quantum yields of the title complexes were calculated by the reference method.The results reveal that all complexes show the characteristic luminescent of central rare earthion. Compared with the Eu(III) complex without substituent group, the complex with electronwithdrawing group possesses lower luminescent intensity and lfuorescence quantum yield，while the complex with electron donating group possesses higher luminescent intensity andlfuorescent quantum yield，the properties of the Tb(III) complex is reverse. Theelectrochemical properties of the title complexes were also investigated by cyclic voltammetry.The results indicate that the HOMO and LUMO energy level of the complex with electrondonating group increases, and that of the complex with electron withdrawing group reduces.(2)Starting from isonicotinic acid and aniline derivatives, a series of salicylaldehydeisonicotinic acid hydrazon derivatives with acetanilide as the end group as well as theircorresponding complexes with Europium or Terbium ion was prepared. The luminescentproperties of the title complexes were investigated by luminescent spectra, and the fluorescentquantum yields of the title complexes were calculated by the reference method. The resultsreveal that all complexes show the characteristic luminescent of central rare earth ion.Compared with the complex without substituent group, the Eu(III) complex with electron withdrawing group possesses lower luminescent intensity and fluorescent quantum yield，while the Eu(III) complex with electron donating group possesses higher luminescentintensity and fluorescence quantum yield, the properties of the Tb(III) complex is reverse. Theelectrochemical properties of the title complexes were also investigated by cyclic voltammetry.The results indicate that the HOMO and LUMO energy level of the complex with electrondonating group increases, and that of the complex with electron withdrawing group reduces.