Synthesis and Physicochemical Properties of Schiff Base Macrocyclic Ligands and Their Transition Metal Chelates

Journal of the Korean Chemical Society

Fouzia Rafat¹  K S Siddiqi¹ 

关键词: Spectroscopic measurements;    Triethylenetetramine;    Macrocyclic ligands;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

Tetraaza Schiff base macrocyclic ligands, L1,L2 and their transition metal chelates have been synthesized and characterized by elemental analyses, IR, electronic, EPR and 1H NMR spectra, TGA and magnetic measurements. The molar conductance of one milli-molar solution of the complexes measured in DMF indicates that the divalent metal complexes are nonelectrolyte while those of trivalent metal ion, are 1:1 electrolytic in the same solvent. The reduction of Racah parameter from the free ion value confirms the presence of considerable covalence of metal ligand sigma bond in the Co(II) and Mn(II) complexes. The EPR spectra of Cu(II) complexes at room temperature shows axial symmetry indicating a dx 2-y 2 ground state with significant covalent character. The thermal analysis suggests that the complexes do not contain water molecules because only the metal is left as residue.

【 授权许可】

Unknown