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)]·H2O}n (1, dpa = 4,4′-dipyridylamine) exhibits a simple 2-D (4,4) rhomboid grid structure. {[Co(1,3-phda)(bpy)]·1.5H2O}n (2, bpy = 4,4′-bipyridine) also possesses a (4,4) layer structure, but with syn–syn bridged {Co2(OCO)2} dimeric kernels serving as 4-connected nodes. {[Co(H2O)4(3-bpmpH2)](1,3-phda)2·8H2O}n (3, 3-bpmp = bis(3-pyridylmethyl)piperazine) manifests cationic 1-D [Co(H2O)4(3-bpmpH2)]n4n+ 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]·2H2O}n (4, 4-bpmp = bis(4-pyridylmethyl)piperazine) has an underlying twofold interpenetrated 658 (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 {Co2(OCO)2} dimers in 2.