新氮杂冠醚衍生物稀土硝酸盐配合物的制备、表征及荧光性质

Synthesis, Characterization and Properties of Triaza-Crown Derivative and their Lanthanide Complexes

通过N3O2大环化合物1,12,15 三氮杂 3,4:9,10 二苯 5,8 二氧杂环十七烷(以下简称为L)与乙酸酐、苯甲酰氯、邻苯二甲酸酐在吡啶介质中反应,合成了N,N′,N″ 三乙酰(L1)、N,N′,N″ 三(2 羧基)苯甲酰(L2)、N,N′,N″ 三苯甲酰(L3)N3O2大环配体,并制备了L1的Sm,Eu,Tb,Dy稀土硝酸盐的配合物。通过元素分析、摩尔电导、热分析、红外的测定对配合物进行了表征。结果表明,L1母体环上的醚氧、酰胺氮均没有参与对稀土离子的配位,并推测了配合物的可能组成。室温下研究了配合物的固体荧光光谱,固态时的配合物(除Sm3+配合物外)均有较强荧光,其中Tb3+配合物的荧光强度最高,表明配体三重态的能量与Tb3+的振动能级更为匹配。在Eu3+的配合物中,强度比η(5D0→7F2 5D0→7F1)=3.7,表明Eu3+处于一非对称配位环境中。

Let N_3O_2 macrocycle 1,12,15-triaza-3, 4∶9,10-dibenzo-5, 8-dioxacycloheptadecane (short as L) react with acetic anhydride, benzoyl chloride and phthalic anhydride in pyridine and chloroform solution. N, N′, N″-triacetyl (L^1), N, N′, N″-tri (2-carboxyl) benzoyl (L^2), N, N′, N″-tribenzoyl (L^3) N_3O_2 macrocycle ligands were synthesized and a series of L^1 complexes with nitrate rare earths (Sm^(3+), Eu^(3+), Tb^(3+) and Dy^(3+)) were also prepared. All these compounds were characterized by elemental analysis, molar conductivity, thermal analysis and IR spectroscopy. The analytical results indicate that oxygen atoms and nitrogen atoms in the ring of L^1 do not coordinate with rare earth ions, and based on these data, a prediction of its possible structure was made. The fluorescence spectra of the complexes in solid phase were studied. The complexes with Eu^(3+), Tb^(3+) and Dy^(3+) have middle luminescence intensity. Among these complexes, complex with Tb^(3+) has the strongest luminescence intensity. It shows that the ligand L^1 triplet state energy matches with Tb^(3+) ()~5D_4 energy level. In the complex with Eu^(3+), η(~5D_0→~7F_2/~5D_0→~7F_1) is 3.7, which indicates that Eu^(3+) is at the center of asymmetric coordination field.