Electrochemical investigation and synthesis of some rhodium dimers

The electrochemical behavior of several rhodium(I) dimers containing two bridging bis(diphenylphosphino)methane or bis(diphenylarsino)methane ligands have been examined using voltammetry and bulk electrolysis in the nonaqueous solvent methylene chloride. The effect of adding coordinating ligands such as halide ions and carbon monoxide to the electrochemical system has been observed.

Several new rhodium(II) dimers have been prepared by the oxidation of the rhodium(I) dimers in the presence of excess chloride or bromide ions. The reduction of a rhodium(I) dimer in the presence of excess carbon monoxide has also been examined. An isolable reduction product has been prepared. The oxidation and reduction products have been characterized using infrared spectroscopy, UV-Visible spectroscopy and elemental analysis.