Synthesis and structure of coordination polymers of Mn²⁺, Cu²⁺, Ag⁺, Zn²⁺ and Cd²⁺ by combination of bipyrazole and diphenate ligands

Five new coordination polymers, (1)(infinity)[Mn(DPA)(Me(4)bpz)(H2O)](I), (1)(infinity)[Cu(DPA)(Me(4)bpz)(2)] center dot H2O(II), (2)(infinity)[Ag-4(OAc)(2)(Me(4)bpz)(3)(H2O)(1:56)] (III), (3)(infinity)[Zn(DPA)(Me(4)bpz)] center dot 0.61 H2O(IV) and (3)(infinity)[Cd(DPA)(Me(4)bpz)(V)[DPA: diphenic acid dianion, OAc: acetate, Me(4)bpz: 3,3',5,5'-tetramethyl-4,4'-bipyrazole], were obtained from acetate hydrates of Mn2+, Cu2+, Ag+, Zn2+ and Cd2+ and a mixed ligand system consisting of Me(4)bpz and diphenic acid by hydrothermal synthesis under similar conditions. Their crystal structures were determined by means of X-ray single crystal structure analysis. Furthermore, the compounds were characterized by means of elemental analysis and IR spectroscopy. The polymers I and II exhibit one-dimensional chain structures with only one type of bridging ligand, whereas the polymers IV and V realize three-dimensional coordination frameworks with diamond topology involving both ligand types as bridging ligands. Compound III contains a two-dimensional cationic framework which is charge compensated by acetate anions. The coordination environments of the metal centers are predominant directly supported by N-H center dot center dot center dot O hydrogen bonds providing further evidence for the bipyrazole-carboxylate supramolecular synthon. (C) 2012 Elsevier B. V. All rights reserved