Cu(ii) frameworks from a “mixed-ligand” approach

Abstract

Employment of di-2-pyridyl ketone and poly-carboxylates in Cu^II chemistry afforded four complex hydrogen-bonded frameworks, one one-dimensional (1D), one 2D and three 3D coordination polymers. Di-2-pyridyl ketone underwent several metal-assisted transformations to yield three Cu^II structural units which, in combination with the poly-carboxylate anions of the trimesic, isophthalic, 5-hydroxy-isophthalic and pyromellitic acids, provided access to extended frameworks by dative or hydrogen bonds. All nine complex frameworks were realized in terms of their topological analysis. The 3D and the 2D polymers consisted of [Cu₂] dimers and were found to be dominated by ferromagnetic interactions. The origin of the ferromagnetic coupling was attributed to the counter complementarity of the simultaneous alkoxo/syn,syn-carboxylate bridges within the dimers.