Synthesis and properties of four transition metal complexes of 5-mercapto-1H-tetrazole-1-acetic acid

Four transition metal complexes with 5-mercapto-1H-tetrazole-1-acetic acid (H(2)mtaa), namely [Zn(mtaa)(H2O)](n) (1), [Cd(mtaa)(H2O)(n) (2), [Mn(Hmtaa)(2)(H2O)(2)](n), (3) and [Co(Hmtaa)(2)(H2O)(2)](n) (4), have been synthesized and characterized by X-ray crystallography. In 1, the left and right-handed helices are interconnected to form a double helix, with further linkages via the mtaa ions to form a two-dimensional layer. While in 2, the mtaa ions bridge the interconnected helices to yield a three-dimensional structure. In 3 and 4, the carboxylate groups bridge metal atoms in a syn-anti conformation, leading to a two-dimensional sheet. In addition, the photoluminescence of 1 and 2 and the magnetic properties of 3 were investigated. (C) 2011 Elsevier Ltd. All rights reserved.