Palladium(II) and Platinum(II) Saccharinate Complexes Containing Pyridine and 3-Acetylpyridine: Synthesis, Crystal Structures, Fluorescence and Thermal Properties

Abstract

New palladium(II) and platinum(II) complexes of saccharinate (sac), trans-[Pd(py)<inf>2</inf>(sac)<inf>2</inf>] (1), cis- [Pt(py) <inf>2</inf>(sac)<inf>2</inf>] (2), trans-[Pd(3-acpy)<inf>2</inf>(sac) <inf>2</inf>] (3) and cis-[Pt(3-acpy)<inf>2</inf>(sac)<inf>2</inf>] (4) (py = pyridine and 3-acpy = 3-acetylpyridine) have been synthesized. Elemental analysis, UV-Vis, IR, NMR and TG/DTA characterizations have been carried out. The structures of 1-4 were determined by X-ray diffraction. The palladium(II) and platinum(II) ions are coordinated by two N-bonded sac ligands, and two nitrogen atoms of py or 3-acpy, forming a distorted square-planar geometry. The palladium(II) complexes (1 and 3) are trans isomers, while the platinum(II) complexes (2 and 4) are cis isomers. The mononuclear species in the solid state are connected by weak intermolecular C-H⋯O hydrogen bonds, C-H⋯π and π⋯π stacking interactions. The platinum(II) complexes show significant fluorescence at the room temperature. © 2011 Elsevier Ltd.