Syntheses, Crystal Structures, Spectroscopic, Fluorescence and Thermal Properties of Silver(I) 5,5-Diethylbarbiturato Complexes With Some Aminopyridines

Abstract

Three new silver(I) complexes of 5,5-diethlybarbiturate (barb), [Ag(barb)(apy)]·H<inf>2</inf>O (1), {[Ag(μ-ampy)][Ag(μ-barb) <inf>2</inf>]}<inf>n</inf> (2) and [Ag(barb)(dmamhpy)] (3) [apy = 2-aminopyridine, ampy = 2-aminomethylpyridine and dmamhpy = 2- (dimethylaminomethyl)-3-hydroxypyridine] have been synthesized and characterized by elemental analysis and FT-IR. Single crystal X-ray diffraction analyses showed that complexes 1 and 3 are mononuclear. In 1, the silver(I) ion is linearly coordinated by a barb anion and a ampy ligand, while a bidentate dmamhpy ligand together with an N-coordinated barb anion forms a trigonal coordination geometry around silver(I) in 3. Complex 2 is a one-dimensional coordination polymer in which silver(I) ions are bridged by ampy ligands, leading to a cationic chain [Ag(ampy)]+n. The [Ag(barb)<inf>2</inf>]- units contains two N-bonded barb ligands, bridging the silver centers in the cationic and anionic units via the carbonyl O atoms. Thus, complex 2 contains two-coordinated and four-coordinated silver ions. All complexes display hydrogen-bonded network structures and exhibit appreciable fluorescence at room temperature. Thermal analysis (TG-DTA) data are in agreement with the structures of the complexes. © 2010 Elsevier B.V. All rights reserved.