Synthesis, structures and thermal stabilities of three 1-D coordination polymers based on flexible polycarboxylates

Three new coordination polymers, [Cu(butca)0.5(bipy)(H2O)] n · 2nH2O (1), [Zn(H2butca) (phen)(H2O)] n · nH2O (2), and [Cd(H2chhca)0.5(phen)(H2O)] n · 2nH2O (3) (H4butca =1,2,3,4-butanetetracarboxylic acid, H6chhca = 1,2,3,4,5,6-cyclohexanehexacarboxylic acid), were prepared and characterized by EA, IR, TG, and X-ray crystallography. Complex 1 is a 1-D double-chain coordination polymer in which tetradentate butca4− coordinates to four Cu(II) ions through four monodentate carboxylates. Complex 2 is a 1-D chain with tridentate H2butca2− coordinating to two Zn(II) ions through monodentate and chelating carboxylates. Complex 3 is a 1-D double-chain coordination polymer. H2chhca4− is octadentate coordinating to four Cd(II) ions through four chelating carboxylates. Hydrogen bonds and π–π stacking interactions play important roles in the formation of supramolecular architectures. The thermal stabilities of 1–3 show dehydrated coordination polymers are thermally stable in the range 260–400°C.