Synthesis, structure, spectroscopic, magnetic and electrochemical studies of NiII phen-dione complex

The first crystal structure of Ni-II phen-dione complex is reported. This compound is [Ni(bpy)(2)(phen-dione)](PF6)(2) (bpy = 2,2'-bipyridine and phen-dione = 1,10-phenanthroline-5,6-dione). The complex has been characterized by elemental analysis, IR and electronic absorption spectroscopy and cyclic voltammetry. The electrochemical behavior and electronic spectrum of [Ni(bpy)(2)(phen-dione)](OAc)(2) has also been studied in buffered solutions at pH between I and 8. ORTEP drawing of [Ni(bpy)(2)(phen-dione)](PF6)(2)(.)2CH(3)CN shows that the coordination geometry around the Ni-II is a distorted octahedron, with bite angles of 78.1-78.8 degrees for all three bidentate ligands and the two pyridyl rings of the bpy ligands are nearly co-planar, as are the two pyridyl rings of phen-dione. (c) 2006 Elsevier B.V. All rights reserved.