Structure and properties of cobalt ortho-phenylenediacetate coordination polymers with rigid dipyridyl ligands

Divalent cobalt coordination polymers containing both ortho-phenylenediacetate (ophda) and rigid dipyridyl ligands 4,4'-bipyridine (bpy) or 1,2-bis(4-pyridyl)ethylene (dpee) display different topologies depending on carboxylate binding mode, tether length, and inclusion of charged species. [Co(ophda)(H2O)(dpee)](n) (1) displays a common (4,4) grid layer motif. Use of the shorter bpy tether afforded {[Co-2(ophda)(2)(bpy)(3)(H2O)(2)][Co(bpy)(2)(H2O)(4)](NO3)(2)center dot 2bpy center dot 7H(2)O}(n) (2) or [Co(ophda)(bpy)](n) (3) depending on cobalt precursor. Compound 2 manifests 5-connected [Co-2(ophda)(2)(bpy)(3)(H2O)(2)](n) pillared bilayer slabs with rare 4(8)6(2) SnS topology and entrained [Co(bpy)(2)(H2O)(4)](2+) complex cations. The 3-D coordination polymer 3 has an uncommon 4,6-connected binodal (4(4)6(2))(4(4)6(10)8) fsc topology, and shows ferromagnetic coupling (J = +1.5(2) cm (1)) along 1-D spiro-fused [Co(OCO)(2)](n) chain submotifs. (C) 2011 Elsevier B.V. All rights reserved.