Synthesis, characterization and X-ray crystal structures of N-2-pyridinyl carbonyl-2-pyridine carboximidate copper(II) complexes

Two copper complexes, [Cu(bpca)(4,4'-bpyH)(H2O)(ClO4)]ClO4 center dot H2O (1) and [Cu-4(bpca)(4)(mpba)]center dot 3H(2)O (2) [bpca = N-2-pyridinylcarbonyl-2-pyridine-carboximidate; mpba = 1,3-phenylenebis(oxamate)] were synthesized and characterized by physico-chemical and spectroscopic techniques. Complex 1 crystallizes in the Triclinic P-1 space group while complex 2 is in the Monoclinic space group C2/c. Bpca acts as a tridentate ligand through its three nitrogen atoms in these species. They exhibit 2D supramolecular architectures through hydrogen bonds and short-distance intermolecular interactions. Magnetic measurements in the range 2-300 K have shown weak antiferromagnetic interactions between the adjacent copper ions in complex 2.