1-1 Metal-Complexes of 2-(2'-Pyridyl)Quinoxaline, a Ligand Unexpectedly Formed by the Reaction between 2-Acetylpyridine and 1,2-Phenylenediamine

The complexes (MLCl2] (M=Co, Ni, Cu, Zn), where L is the new ligand 2-(2'-pyridyl)quinoxaline derived unexpectedly from 2-acetylpyridine and 1,2-phenylenediamine, were isolated. The ligand and its complexes have been characterized by a variety of physical and spectroscopic techniques. L behaves as a bidentate chelating ligand in the monomeric pseudotetrahedral Zn(II) compound; all three nitrogen atoms of L are involved in coordination in the polymeric Co(II), Ni(II) and Cu(II) complexes giving five-coordinate (Co(II)) or six-coordinate (Ni(II), Cu(II)) structures. Inorganica Chimica Acta