Synthesis And Characterization Of Complexes Based On Nitroxide Nitronyl-metal Ions

The design and synthesis of metal complexes with nitronyl nitroxide radical isone of the most attractive fields in the molecular-based magnetic materials. In orderto investigate three correlation between the structure and magnetic properties, Threeligands have been synthesized.Useing three ligands, design and synthesis fivemetal-nitoxide nitronyl complexes.All their single crystals have been determined byX-ray diffraction technique. They have been characterized by element analyses, IR,ESR，UV and other methods.Three ligands are O-carboxyphenyl Nitroxide nitronyl,2-Quinoxalin Nitroxidenitronyl,2-Phenyl-1,2,3-triazole-4-nitroxide nitronyl. Four of these complexes areZn(acac)2(NIT-2-QN)2·[CH2Cl2]2,Co(acac)2(NIT-2-QN)2·[CH2Cl2]2,Mn(acac)2(NIT-2-QN)2·[CH2Cl2]2,Ni(acac)2(NIT-2-QN)2·[CH2Cl2]2,(NIT-2-QN=2-(2-Quinoxalin)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, acac=acetylacetone). These fourcomplexes with metal ions to form a six-coordinated central atom octahedral structure,two acetyl acetone to form a bidentate chelating ligand and two nitrogen atoms fromtwo radicals NITR. The other complex is La(hfac)3(NITPhtrz)·(H2O)(hfac=hexafluoroacetylacetonate,NITPhtrz=2-Phenyl-1,2,3-triazole-4-nitroxidenitronyl). The La(III) ion is eight-coordinated with six oxygen atoms of three hfacanions, one oxygen atom from NITR and the other from H2O.Many coordination compounds made of metal and nitronyl nitroxide radicalshave been studied. In addition, we also process thermodynamic analysis for thecomplexes, and derived the thermal decomposition which provide a scientificexperiment basis for these new functional complexes magnetic materials.