ACS Omega 2018 Nov 27;3(11):16021-16027. Epub 2018 Nov 27.
Department of Chemistry, Cleveland State University, 2121 Euclid Avenue, Cleveland, Ohio 44114, United States.
Removal of chloride from CoCl with TlPF in acetonitrile, followed by addition of excess nitrosobenzene, yielded the eight-coordinate cobalt(II) complex salt [Co{Ph(O)NN(O)Ph}](PF), shown by single-crystal X-ray analysis to have a distorted tetragonal geometry. The analogous treatment of the bipyridyl complex Co(bpy)Cl yielded the mixed-ligand cobalt(II) complex salt [Co(bpy){Ph(O)NN(O)Ph}](PF), whose single-crystal X-ray structure displays a trigonal prismatic geometry, similar to that of the iron(II) cation in the previously known complex salt [Fe{Ph(O)NN(O)Ph}](FeCl). The use of TlPF to generate solvated metal complex cations from chloride salts or chlorido complexes, followed by the addition of nitrosobenzene, is shown to be a useful synthetic strategy for the preparation of azodioxide complex cations with the noncoordinating, diamagnetic PF counteranion. Coordination number appears to be more important than electron count in determining the geometry and metal-ligand bond distances of diphenylazodioxide complexes.