Synthesis, solid-state structure and supramolecularity of [Cu(pyterpy)2](ClO4)2

The copper(II) polypyridyl complex [Cu(pyterpy)2](ClO4)2 (3) (pyterpy = 4′-(4-pyridyl)-2,2′:6,2″-terpyridine) was prepared by the reaction of pyterpy (1) with stoichiometric amounts of [Cu(ClO4)2·6H2O] (2). The progress of the reaction was controlled by FT-IR and UV–vis spectroscopy. The title complex crystallized in the tetragonal space group I4(1)/a with unit cell dimensions of a = 8.6277(1), b = 8.6277(1), c = 57.6398(10) Å, V = 4290.55(12) Å3, and Z = 4. The structure of 3 in the solid-state consists of discrete [Cu(pyterpy)2]+ ions with copper(II) in a distorted octahedral environment setup by two meridional coordinated tripodal 4′-(4-pyridyl)-2,2′:6,2″-terpyridine ligands of which the pyridyl unit stays free. Face-to-face π-interactions between terminal coordinated terpy C5N rings link adjacent [Cu(pyterpy)2]2+ units resulting in the formation of a 2D-polymer. The geometrical-to-geometrical centroid distance (d) is 3.568 Å.