Uncommon coordination modes of 4-methylimidazole in [Zn(4-Meim)(2)(5-Meim)(2)]sq center dot 3H(2)O

Abstract

A novel Zn(II) complex, [Zn(4-Meim)(2)(5-Meim)(2)]sq center dot 3H(2)O (1), (H(2)sq = squaric acid, 4-Meim = 4-methyl-imidazole and 5-Meim = 5-methylimidazole) has been synthesized and characterized by elemental, spectral (IR), thermal analyses and single crystal X-ray diffraction techniques. The Zn(II) ion center accommodates two binding types of the 4(5)-Meim ligand in same coordination sphere, which is a very unique example of the linkage isomers. The sq counterion interacts each other though water bridges by strong hydrogen bonds forming a zig-zag chain along the b-axis and generate R-4(4)(14) motif. The adjacent chains are connected by the water molecule forming a R-8(8)(22) aperture. (C) 2009 Elsevier B.V. All rights reserved.