Synthesis and structure of a cobalt dicyanamide chain coordination polymer incorporating a long-spanning hydrogen-bonding capable diimine with a novel binodal (4,6)-connected supramolecular topology

The 1D chain coordination polymer [Co(dca)(2)(4-bpmp)(2)(H2O)2](n) (1, dca=dicyanamide, 4-bpmp=bis(4-pyridyl methyl)piperazine) has been prepared by a solution phase method and characterized by single-crystal X-ray diffraction, IR and elemental analysis. The dca ligand adopts a relatively uncommon monodentate binding mode. Interchain hydrogen-bonding mechanisms between the unligated nitrogen atoms of the pendant dca ligands and aqua ligands promote formation of a sawtooth (4,4) supramolecular layer. In turn. hydrogen-bonding interactions between aqua ligands and piperazinyl nitrogen atoms within the 4-bpmp tethers result in a simple yet unique (4,6)-connected supramolecular network with (4(2)5(2)6(2))(4(2)5(6)6(4)7(3)) topology. (C) 2009 Elsevier B.V. All rights reserved.