DINUCLEAR TRIPOD COBALT COMPLEXES WITH BR IDGING 1,4,5,8-TETRAOXONAPHTHALENE AND 1,4,9,10-TETRAOXOANTHRACENE LIGANDS - STRUCTURES, SPECTROSCOPIC, MAGNETIC, AND ELECTROCHEMICAL PROPERTIES

The syntheses, structures, optical, magnetic, and redox properties of dinuclear tripodcobalt(II) complexes [tripod = CH3C(CH(2)PPh(2))(3)] w ith briding 1,4,5,8-tetraoxonaphthalene 1(2-) and 1,4,9,10-tetraoxoant hracene 2(2-) are described. UV/Vis/NIR spectroscopy indicates interac tion between the ligand and the metal orbitals. The magnetic interacti ons involving the two cobalt(II) centers and the bridging ligand are c haracterized by EPR spectroscopy and magnetic measurements and are ana lyzed in terms of qualitative Molecular Orbital calculations. The redo x chemistry of these complexes is investigated by cyclic voltammetry a nd interpreted as metal-based oxidations and ligand-based reductions.