Effect of pendant arm position and length on the structure and properties of nickel aromatic dicarboxylate coordination polymers incorporating a kinked organodiimine

Hydrothermal synthesis has afforded three nickel coordination polymers incorporating both aromatic dicarboxylates and the kinked and hydrogen bonding capable organodiimine 4,4'-dipyridylamine (dpa). These were characterized by single-crystal X-ray diffraction, infrared spectroscopy, and thermogravimetric analysis. [Ni(1,2-phda)(dpa)(H2O)] (1,2-phda = 1,2-phenylenediacetate, 1) displays (4,4) rhomboid grid-like 2D layers that aggregate into 3D through O-H center dot center dot center dot O hydrogen bonding. Shortening one of the pendant arms of the dicarboxylate ligand resulted in a shift to (6,3) herringbone style 2D coordination layer motifs in {[Ni(hmph)(dpa)]center dot 1.33H(2)O}(n) (hmph = homophthalate, 2), which stack in an AA'B pattern. [Ni(1,3-phda)(dpa)(mu-H2O)(0.5)](n) (1,3-phda = 1,3-phenylenediacetate. 3) manifests a canted Primitive cubic type coordination polymer lattice constructed from Binuclear [Ni-2(mu-H2O)] kernels linked into 3D through tethering 1,3-phda and dpa ligands. Analysis of the variable temperature magnetic susceptibility of 3 indicated the presence of antiferromagnetic superexchange within its Binuclear Units (g = 2.290(2), J = -4.21(2) cm(-1)). (C) 2008 Elsevier Ltd. All rights reserved.