(Pentane-2,4-dionato-?2O,O')(pyridin-2-amine-?N1)copper(II) and (pentane-2,4-dionato-?2O,O')(pyrimidin-2-amine-?N1)copper(II)

The title compounds, [Cu(C5H7O2)2(C5H6N2)], (I), and [Cu(C5H7O2)2(C4H5N3)], (II), were prepared by the reaction of bis(pentane-2,4-dionato-?2O,O')copper(II) with pyridin-2-amine and pyrimidin-2-amine, respectively. From a chemical point of view, it is interesting that no Schiff base formation was observed. The compounds are isostructural, with both having a square-pyramidal coordination of the CuII atom and intramolecular NH...O hydrogen bonding. The additional N atom of the pyrimidin-2-amine ligand is not involved in hydrogen bonding or in metal coordination. In the crystal structure, chelate rings are involved in pp interactions and molecules of (I) are linked together via NH...O hydrogen bonds.