One- and two-dimensional cobalt benzenecarboxylate coordination polymers containing a kinked organodiimine: Synthesis, structure, and magnetic properties

Hydrothermal reaction of cobalt nitrate, phenylmalonic acid, and 4,4′-dipyridylamine (dpa) resulted in formation of the coordination polymer [Co2(phac)4(dpa)2(H2O)] (1, phac = phenylacetate), where the phac ligand is formed in situ by the decarboxylation of phenylmalonic acid. Binuclear [Co2(phac)4(H2O)] units with both bridging and monodentate benzenecarboxylate ligands are linked into a two-dimensional (4, 4) rhomboid grid network via dpa tethers within the structure of 1. Use of benzoate as the anionic component allowed the formation of [Co(benzoate)2(dpa)2] (2), which manifested a dpa-linked one-dimensional chain coordination polymer motif with pendant monodentate and chelating carboxylates. Modest antiferromagnetic coupling was observed within the binuclear units in 1.