The formation of mononuclear iron(II) and zinc(II) complexes and dinuclear mesocates of copper(II) with pyrazine-bis(bipyridine) ligand

Abstract By the self-assembly of 2,3-bis(6′-methyl-2,2′-bipyridin-6-yl)pyrazine ligand L and Fe(II), Zn(II) and Cu(II) metal salts two different supramolecular complexes were obtained: mononuclear [ML 2 ]X 2 complexes (where M = Fe(II) and X = Cl − ( 1 ) or BF 4 − ( 2 ), M = Zn(II) and X = NO 3 − ( 3 ) or X = CF 3 SO 3 − ( 4 )) and dinuclear [Cu 2 L 2 ]X 4 (X = BF 4 − ( 5 ) or X = CF 3 SO 3 − ( 6 )). Fe(II) 2 and Cu(II) 5 complexes have been characterized by X-ray crystallography. In Cu(II) complex 5 two metal centers have opposite chirality, what give rise to formation of achiral meso -helicate.