Syntheses, crystal structures and properties of tetrahydrofuran-2,3,4,5-tetracarboxylato bridged copper(II) coordination polymers with alkali metals

Four tetrahydrofuran-2,3,4,5-tetracarboxylato bridged copper(II) coordination polymers with alkali metals, Na2[Cu(H2O)(THFTC)]·5H2O 1, K2[Cu3(H2O)2(THFTC)2]·9H2O 2, Rb2[Cu3(H2O)2(THFTC)2]·6H2O 3 and Cs2[Cu3(H2O)2(THFTC)2]·6H2O 4 (H4THFTC = tetrahydrofuran-2,3,4,5-tetracarboxylic acid) were prepared from reactions of Cu(NO3)2·3H2O, tetrahydrofuran-2,3,4,5-tetracarboxylic acid and alkali hydroxide or carbonate at pH 5.0–6.0 under ambient conditions. Compound 1 features 2D (33·43·54) topological layers generated from six-coordinated Cu2+ cations interlinked by (THFTC)4− anions, and the resulting layers are ecliptically stacked along [1 0 0] direction to form lozenge-shaped and octagonal channels filled with Na+ ions and lattice H2O molecules. In 2–4, both penta- and hexa-coordinated copper(II) ions are bridged by tetracarboxylate anions to form negatively charged 2D layers formulated as 2∞[Cu(H2O)2L3/2]2− with the corresponding alkali metal cations (K+, Rb+ or Cs+ ions) and hydrogen bonded lattice H2O molecules sandwiched between them. Additionally, the results about i.r. spectroscopic, thermal characterizations and magnetic properties are presented.

Four tetrahydrofuran-2,3,4,5-tetracarboxylato bridged copper(II) coordination polymers with alkali metals, Na2[Cu(H2O)(THFTC)]·5H2O 1, K2[Cu3(H2O)2(THFTC)2]·9H2O 2, Rb2[Cu3(H2O)2(THFTC)2]·6H2O 3 and Cs2[Cu3(H2O)2(THFTC)2]·6H2O 4 (H4THFTC = tetrahydrofuran-2,3,4,5-tetracarboxylic acid) were prepared and feature 2D layers generated from Cu(II) ions interconnected by tetrahydrofuran-2,3,4,5-tetracarboxylate anions.Figure optionsDownload as PowerPoint slide