Divalent metal 1,3-phenylenediacetate coordination polymers with rigid or flexible dipyridyl tethers: Chains, layers, and interpenetrated networks

Hydrothermal synthesis has afforded four divalent metal 1,3-phenylenediacetate (1,3-phda) coordination polymers containing different dipyridyl-type ligands. {[Cu(1,3-phda)(dpa)(H2O)]center dot H2O}(n) (1, dpa = 4,4'-dipyridylamine) exhibits a simple 2-D (4,4) rhomboid grid structure. {[Co(1,3-phda)(bpy)]center dot 1.5H(2)O}(n) (2, bpy = 4,4'-bipyridine) also possesses a (4,4) layer structure, but with syn-syn bridged {Co-2(OCO)(2)} dimeric kernels serving as 4-connected nodes. {[Co(H2O)(4)(3-bpmpH(2))](1,3-phda)(2)center dot 8H(2)O}(n) (3, 3-bpmp = bis(3-pyridylmethyl) piperazine) manifests cationic 1-D [Co(H2O)(4)(3-bpmpH(2))](n)(4n+) chains linked into higher dimensionality by unligated 1,3-phda anions and curled tetrameric water molecule units. {[Ni(1,3-phda)(4-bpmp)(H2O)(2)]center dot 2H(2)O}(n) (4,4-bpmp = bis(4-pyridylmethyl) piperazine) has an underlying twofold interpenetrated 6(5)8 (cds) 3-D network topology. Variable temperature magnetic susceptibility studies revealed the presence of weak antiferromagnetic coupling and zero-field splitting (J = -1.65(4) cm(-1) and D = 30.9(7) cm(-1) with g = 2.20(1)) within the {Co-2(OCO)(2)} dimers in 2. (C) 2010 Elsevier B.V. All rights reserved.