Synthesis, characterization and X-ray crystal structures of two five-coordinate ternary copper(II) complexes containing acetylacetonate with 1,10-phenanthroline and 2,9-dimethyl phenanthroline

The synthesis, characterization and crystal structures of two mixed ligand copper(II) complexes containing acetylacetonate (acac) with 1,10-phenanthroline (phen) or 2,9-dimethyl-1,10-phenanthroline (dmph) are reported. Namely, they are [Cu(acac)(phen)(NO3)]·H2O (1) and [Cu(acac)(dmph)(NO3)] (2). In both complexes, the copper atom has an approximate square-pyramidal coordination geometry with the two nitrogen atoms from (phen) or (dmph), and the three oxygen atoms (two from (acac), one from the nitrate ion). In complex 1, the two nitrogen atoms and the two oxygen atoms of acetylacetonate occupy the basal plane and the nitrate group is in the apical position. In complex 2, a steric hindrance introduced by the two methyl groups of (dmph) is released by accommodating one nitrogen atom of (dmph) in the apical position while the nitrate group accommodates itself in the equatorial plane. Furthermore, stacking interactions between the (phen) rings from the different asymmetric units are observed. The results of IR, UV-Vis and magnetic measurements are discussed. © 2001 Elsevier Science B.V. All rights reserved.