Two copper(II) complexes containing the common chain structures with different charge states

Two one-dimensional copper(II) coordination polymers constructed from 2-hydroxypyrimidine-4,6-dicarboxylic acid (H3hpdc), [Cu2(Hhpdc)2(NH3)2]·2NH3·H2O (1) and [Cu(NH3)4(H2O)][Cu2(hpdc)2(NH3)2]·2H2O (2), have been synthesized and characterized by X-ray single-crystal diffraction analysis and variable temperature magnetic susceptibility measurements, etc. Despite the different deprotonated forms of H3hpdc in 1 and 2, hydroxy-oxo tautomerism optimizes the coordination preferences of the ligands, presenting unique coordination polymers containing similar chain structures with different charge states. Moderate antiferromagnetic coupling interactions between adjacent Cu (II) ions are observed in two compounds.