Cu(II), Zn(II) and Cd(II) Complexes with Picolinamide Azine Derived from 2-Acetyl Pyridine and 2-Picolinamide Hydrazone: Crystal Structures and Fluorescence Properties

Three complexes [(Cu)(L)(Cl)(2)](1), [(Zn)(L)(Cl)(2)] (2) and {[(Cd)(2)(L)(I)(4)]}(n) (3) (L is derived from 2-acetyl pyridine and picolinamide hydrazone) have been synthesized and characterized by single-crystal X-ray diffraction, elemental analysis and IR spectroscopy. X-ray diffraction analysis results show that complexes 1 and 2 are isostructural. The coordination geometry of the metal ion in each complex is a distorted trigonal biyramid with three nitrogen atoms from the ligand L and two chloride anions. However, in complex 3, two adjacent five-coordinated Cd(I) ion are connected by two bridged mu(2)-I- anions, resulting in the formation of one-dimensional chain along c axis. In addition, the thermal stability and luminescent properties of the complexes are also studied in detail. CCDC: 1412923, 1; 1412924, 2; 1412925, 3.