Synthesis, characterization and crystal structure of [Cu(2-pic)2Br2][(2-picH)2]

The reaction of the pyridyne-2-carboxylate acid with CuBr2 leads to the formation of the compound of the formula [Cu(2-pic)2Br2][(2-picH)2], where 2-pic is pyridyne-2-carboxylate ion and 2-picH is cation of the pyridyne-2-carboxylate ion with deprotonated carboxyl oxygen and protonated pyridyl nitrogen atoms. The compound was characterized by infrared, ligand field and EPR spectroscopy and magnetic properties and also the single-crystal structure was determined. The structure of [Cu(2-pic)2Br2]2− anion shows a strongly tetragonally distorted octahedral stereochemistry (CuN2O2Br2 chromophore), resulting from the bidentate N,O-bonded two chelate ligands and two bromide ions in an axial position.