The First Bis(Orotato-N,O) Cadmium Complex with Monodentate Protonated Ethylenediamine Ligands: Synthesis, Spectrothermal Properties of a Cadmium(II)-Orotato Complex with Ethylenediamine - Crystal Structure of trans-[Cd(HOr)2(enH)2] · 2H2O and cis-[Cd(H2O)2(Phen)2](H2Or)2 · 2H2O

Abstract

Two new orotic acid complexes of cadmium(II) with protonated monodentate ethylenediamine and 1,10-phenanthroline were synthesized and characterized by X-ray diffraction techniques. trans-[Cd(HOr)<inf>2</inf>(enH)<inf>2</inf>] · 2H<inf>2</inf>O (1) (enH = ethylenediammonium) crystallizes in the triclinic system, space group P over(1, ̄), and the Cd(II) ion exhibits a distorted octahedral coordination by bis(bidentate) orotate anions and two protonated monodentate ethylenediamine ligands. The individual molecules of 1 are held together by N-H⋯O and O-H⋯O hydrogen bonds, forming a three-dimensional network. The supramolecular compound cis-[Cd(H<inf>2</inf>O)<inf>2</inf>(phen)<inf>2</inf>](H<inf>2</inf>Or)<inf>2</inf> · 2H<inf>2</inf>O (2) (phen = 1,10-phenanthroline) crystallizes in the monoclinic system, space group C2/c and the Cd(II) ion is coordinated by two symmetry related aqua ligands together with a pair of symmetry related bidentate 1,10-phenanthroline molecules, and exhibits a distorted octahedral coordination. The unique orotate anion in the asymmetric unit has a single negative charge. The coordinated water molecules link the orotate ions to the metal complex via O-H⋯O hydrogen bonds. Each uncoordinated water molecule is hydrogen bonded to orotate ions through O-H⋯O hydrogen bonds. Thus, an extensive network of hydrogen bonds stabilizes the crystal structure and forms an infinitive three dimensional lattice. The IR spectrum and thermal analysis of 1 is described. The decomposition reaction take places in the temperature range 20-1000 °C in static air atmosphere. © 2007 Elsevier Ltd. All rights reserved.