Ternary Complexes of Cu (II), Ni (II), Co (II) and La (III) Ions with 2-[(Pyridin-2-Ylmethylidene) Amino] Phenol and Heterocyclic Nitrogen Base

Schiff bases are one of the most prevalent and important of the mixed donor systems in the field of coordination chemistry.2-Aminopyridines also serve as useful chelating ligands in a variety of inorganic and organ metallic applications [1,2].Amino pyridines and their derivatives in most cases act as monodentate ligands which coordinate the metal ions through the nitrogen of the ring [3,4]. Also, amino pyridines have been proposed as drugs for the treatment of many diseases such as myocardial infarction as antithrombus agents and diarrhea as antimicrobial agents [5,6]. Moreover, amino pyridines are commonly present in synthetic and natural products [7]. They form repeated moiety in many large molecules with interesting photophysical, electrochemical and catalytic applications [8].The complexes with different types of heterocyclic such asamines, imines, oxazole, imidazole and ligands containing pyridine play an important role in biology and medicine areas. These ligands are often used in medicine, because of their pharmacological properties such as antibacterial activity [9,10].On the other hand, complexes of Schiff base ligands derived from 2pyridinecarboxaldehyde derivatives with some transition metals such asCu(II), Co(II), Cd(II) and Zn(II) show significant biological activity [11,12]. Moreover, luminescent compounds are attracting much current research interest because of their many applications including emitting materials for organic light emitting diodes, light harvesting materials for photo catalysis and fluorescent sensors for organic or inorganic analytes [13-17].The decomposition of hydrogen peroxide has been used as a model reaction for the investigation of the catalytic activity of various metal complexes [18]. For example, the catalytic activity of copper (II) complex of chitosan derivative which derived from chitosan and 4, 6-diacetylresorcinol was investigated on hydrogen peroxide decomposition [19]. Also, the mixed ligand complex [Fe(2-AP)(Ala)Cl3]4H2O (2-AP = 2-acetylpyridine, Ala = alanine) catalyzed the decomposition of H2O2 and O2 was evolved [20]. Herein, we report the transition metal complexes of Schiff base derived from the condensation of 2-pyridinecarboxaldehyde with 2aminophenol.The ternary complexes were obtained by reaction with 2-aminopyridine. The structural features of these complexes were examined by analytical and spectral techniques. Abstract: A new ternary Schiff base transition metal complexes of general formula [M(HL)(2-AP)Cl2].H2O where M= Cu(II), Ni(II) and Co(II) ions in addition to the complex [La(HL)(2-AP)(NO3)2].NO3have been prepared by template synthesis. The synthesized metal complexes were characterized using spectroscopic techniques. The molar conductivities of the complexes in DMF indicated non electrolytic behavior except La(III) complex.IR spectra show that the Schiff base (HL) is coordinated to the metal ions in a tridentate manner with NNO donor sites of the pyridine-N, azomethine-N and phenolic-O,while 2-aminopyridine coordinated to the metal ions via its pyridine-N. The ligand (HL) and its mixed ligand complexes exhibited intraligand (-*) fluorescence and can potentially serve as photoactive materials. The catalytic activity of the complexes towards hydrogen peroxide decomposition reaction was investigated. Both the ligand (HL) and mixed ligand complexes have been screened for antibacterial activities.