邻香兰素缩对甲苯胺Schiff碱稀土配合物的合成、晶体结构和热分解动力学机制

Syntheses, Crystal Structures and Thermal Decomposition Mechanisms of Rare Earth Complexes with A Schiff Base Derived from o-Vanillin and p-Toluidin

合成了2-甲氧基-6-[（4-甲基苯基）亚胺甲基]-苯酚Schiff碱（C15H15NO2,简写为HL）的3个稀土配合物[Pr（NO3）3（HL）2]（1）,[Nd（NO3）3（HL）2]（2）,[Er（NO3）3（HL）2]·0.5H2O（3）,结构通过单晶X射线衍射分析确定,并用元素分析、摩尔电导、 IR、 1HNMR和紫外可见光谱进行表征.化合物1～3中,Schiff碱作为二齿配体与中心离子发生配位,稀土离子均采用十配位的双帽四方反棱柱构型,分别与两个Schiff碱中的4个氧原子、 3个硝酸根中的6个氧原子发生配位.通过TG-DTG研究了配合物的热分解过程,用非等温动力学方法研究了配合物3的热分解动力学机制.

Three title complexes, [ Pr （NO3）3 （ HL）2 ] （1）, [Nd（NO3）3（HL）2]（2）, [Er（NO3）3（HL）2]·0.5H2O（3）, were synthesized from the reaction of a Schiff base ligand 2-[ （4-methylphenylimino） methyl ]- 6-methoxyphenol （C15H15NO2, HL）, obtained by condensation of o-vanillin and p-toluidine, with Ln（NO3）3·nH2O. They were characterized by single-crystal X- ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis, ^1H NMR spectra, thermal analysis. The title complexes are neutral molecules in which the central Ln （Ⅲ） ion is ten-coordinated in biapical anti-tetragonal prism geometry, with four oxygen atoms of two bidentate Schiff base ligands via phenolic hydroxy and methoxy groups and six oxygen atoms of three bidentate NO3^- anions. Additionally, the kinetic mechanism of thermal decomposition of the complex 3 was determined with a TG-DTG curves by integral and differential methods. The functions of reaction mechanism of thermal decomposition and effect equations of kinetic compensation were obtained.