Two-dimensional divalent metal/pimelate coordination polymers incorporating dipodal organodiimines: Crystal structures, thermal properties, and magnetic studies

Hydrothermal synthesis has afforded a series of 2-D coordination polymers incorporating the flexible α,ω-dicarboxylate pimelate ligand (pim) and either the kinked organodiimine 4,4′-dipyridylamine (dpa) or its conformationally flexible congener 1,3-di-4-pyridylpropane (dpp).[M(pim)(dpa)(H2O)]n (M = Co, 1-Co; M = Ni, 1-Ni) both display puckered (4,4) rhomboid grid-like 2-D layers that aggregate into 3-D through O–H⋯O hydrogen bonding. {[Cu2(pim)2(dpa)2] · 5H2O}n (2) possesses 2-D slab motifs constructed from the linkage of [Cu2(pimelate)2]n ribbons and [Cu(pimelate)]n double chains through dpa tethers, entraining discrete water molecule chains with D(8) classification. Employing the longer dpp tether resulted in [Ni(pim)(dpp)]n (3), which manifested a doubly interpenetrated 2-D (4,4) grid layer morphology. Analysis of the variable temperature magnetic susceptibility of 1-Ni indicated the presence of zero-field splitting as well as possible weak antiferromagnetic coupling between Ni atoms in adjacent layer subunits. In contrast, 2 manifested apparent intradimer ferromagnetic interactions with underlying interdimer antiferromagnetic coupling.

Hydrothermal synthesis has afforded coordination polymers incorporating the flexible pimelate ligand (pim) and either 4,4′-dipyridylamine (dpa) or 1,3-di-4-pyridylpropane (dpp).[M(pim)(dpa)(H2O)] (M = Co, Ni) displays (4,4) rhomboid grids. {[Cu2(pim)2(dpa)2] · 5H2O} (2) possesses slab motifs with water molecule chains. [Ni(pim)(dpp)] manifests doubly interpenetrated (4,4) grids. Thermal and magnetic properties are reported.Figure optionsDownload as PowerPoint slide