A one-dimensional assembly of copper(II) polyhedra via dual use of hydrogen-bonding and π–π interaction

A copper(II) complex [Cu(Hpadh)Cl2] with pyridine-N, imine-N and amide-O coordinating 2-pyridine-carboxaldehyde 4-dimethylaminobenzoylhydrazone (Hpadh) has been synthesized and structurally characterized. In the solid state, each square–pyramidal Cu(Hpadh)Cl2 unit is connected to one neighbour by a pair of hydrogen bonds between the amide-H and the apical chloride and to the other by a couple of π–π interactions between the aromatic rings of the coordinated ligands forming a novel chain-like arrangement of copper(II) centres with successive long and short Cu···Cu distances. Variable temperature (300–18 K) magnetic susceptibility measurements showed that the complex is essentially Curie paramagnetic.