[Cu(phdpa)Cl]+ (phdpa=bis(2-pyridylmethyl)aniline): a moiety of unusual stability in some 1:1 Cu(II) complexes of phdpa. Synthesis and X-ray crystal structures of [Cu(phdpa)Cl2] and [Cu2(phdpa)2Cl3]PF6·0.5MeOH

1:1 copper(II) complexes of bis(dipyridylmethyl)aniline (phdpa) of various kinds, with chloride and PF6 − as anions, were synthesized and characterized by elemental analysis, IR spectroscopy and X-ray structure crystallography. The crystal structures of [Cu(phdpa)Cl2] (I) and [Cu2(phdpa)2Cl3]PF6·0.5MeOH (II) showed that the metal atoms are five-coordinated and that the structures are also stabilized by a triple intramolecular hydrogen-bond system. The resulting unusual stability of the [Cu(phdpa)Cl]+ moiety influences the exchange properties with PF6 − of compound I, which gave complexes where the cationic group is maintained also under drastic reaction conditions.