镧系与邻氨基苯甲酸型Schiff碱配合物的合成、表征及催化活性

Synthesis and Characterization of New Lanthanide Complexes with N-(2, 4-Dihydroxyhenzalidene)-anthranilic Acid and Their Catalytic Activity

本文合成2,4-二羟基苯甲醛缩邻氨基苯甲酸Schiff碱(H_3L),以改进的合成方法得到此配体与镧系元素形成的九种新配合物。经分析确定其组成为[Ln(H_2L)_2NO_3],(Ln=La、Pr、Nd、Sm、Gd、Dy、Ho、Er、Yb)。以热重-差热分析、紫外、红外光谱以及核磁共振谱等表征,证明该Schiff碱具有稳定的分子内氢键并以三齿形式同镧系离子形成稳定的共轭双六元螯合环。经研究表明,此系列配合物对甲基丙烯酸甲酯的聚合有明显的催化活性。

A new Schiff base (H_3L) has been obtained through the reaction of 2, 4-dihydroxybenzaldehyde with anthranilic acid in alcohol. Complexes of this Schiff base with a series of Ln (Ⅲ) (Ln=La, Pr, Nd, Sm, Gd, Dy, Ho, Er, Yb), which have not been reported previously, were synthesized using an improved method. The complexes [Ln(H_2L)_2NO_3] have been characterized by elemental analysis, molar conductivity, TG-DTA, IR-, UV-spectra and NMR measurements. The ligand, which aets as tridentate in the complexes, forms a double six-membered ring structure with Ln (Ⅲ). Experimental results show that these complexes can be used as a new catalyst in the polymerization of methyl methacrylate (MMA).