Controlling the geometry of Cu(ii) tectons to build one-dimensional hydrogen bonded chains

Abstract

Through an analysis of the Cambridge Structural Database, CSD, we found that Cu(II) complexes with planar tridentate amines and two monodentate ligands tend to present a square pyramidal geometry. We decided to test the 2,2′ : 6′2″-terpyridine, trpy, as a ternary ligand to build [Cu(trpy)(CA)(H₂O)] tectons, CA representing an organic carboxylate, in the supramolecular synthesis of an H-bonded coordination compound. Six new crystal structures are reported and analyzed with other similar compounds reported in the CSD. In all of them a square pyramidal geometry and 1-D supramolecular structures are obtained through an O–H⋯O hydrogen bond between the coordinated water molecule and one O atom from the carboxylate ligand. Thus, molecular and supramolecular control over the Cu(II) complexes is achieved.