Synthesis, Crystal Structure and Magnetic Properties of Diaqua(1,10-Phenanthroline-N,N')-Hydrogenmaleatocopper(Ii) Hydrogenmaleate Monohydrate

Abstract

Reaction of freshly-prepared CuCO3, phenanthroline monohydrate and maleic acid in CH3OH/H2O(1 : 1 v/v) at pH=2.13 yielded diaqua(1,10-phenanthroline-N,N')hydrogenmaleatocopper(II) hydrogenmaleate monohydrate, [Cu(phen)(H2O)2(C4H3O4)](C4H3O4)(H2O), which consists of [Cu(phen)(H2O)2(C4H3O4)]+ complex cations, hydrogenmaleate anions and lattice H2O molecules. Within the complex cations, the Cu atoms are each square-pyramidally coordinated by two N atoms of one chelating phen ligand and three O atoms of two H2O molecules and one hydrogenmaleato ligand with one H2O molecule at the apical position (d(Cu-N) = 2.001, 2.009 Å, equatorial d(Cu-O) = 1.966 Å and axial d(Cu-O) = 2.235 Å). Through hydrogen bonding, the complex cations, hydrogenmaleate anions and lattice H2O molecules are assembled into 1D chains, which are held together by weak Cu···O interactions (3.139 Å) to form corrugated 2D layers. Significant π-π stacking interactions between neighboring phen ligands leads to supramolecular assembly of the 2D layers. Over the temperature range 5-300 K, the complex obeys the Currie-Weiss law with an effective magnetic moment of 1.78 BM at room temperature.