Crystal structures of two polymeric 1,5-naphthalenedisulfonate-coordinated transition metal complexes

Two 1,5-naphthalenedisulfonate(1,5-nds)-coordinated polymeric complexes [Cu(1,5-nds) (H2O)4] n and [Cd(1,5-nds)(H2O)2] n were synthesized and their structures characterized by single-crystal structure analysis. The Cu(II) complex [Cu(1,5-nds)(H2O)4] n is obtained both from CuCl or CuCl2 reacting with 1,5-naphthalenedisulfonic acid at 80∘C. It is a one-dimensional polymer in which Cu(II) is coordinated by four water molecules and two sulfonate oxygen atoms in the trans positions. The interaction between sulfonate and Cu(II) is different in complexes obtained from different reaction temperature. While the three-dimensional Cd(II) complex [Cd(1,5-nds)(H2O)2] n is a polymorph of the reported two-dimensional layer structure, in which Cd(II) is coordinated by two water molecules in the trans positions and four different sulfonate groups, the same as that observed in the two-dimensional polymorph. However, the 1,5-nds ligands connect Cd(II) centers belonging to different layers, resulting in the three-dimensional framework.