Chemical Properties
Clear orange to gold colored solution
Uses
Oxidizing agent similar to osmium tetroxide, but more difficult to handle. The solvents normally employed in OsO4 oxidations (ether, benzene, pyridine) cannot be used because of their violent reaction with RuO4. Only CCl4 is recommended: Djerassi, Engle, J. Am. Chem. Soc. 75, 3838 (1953).
Hazard
Fire risk in contact with organic materials.
Preparation
Ruthenium tetroxide can be conveniently handled as a carbon tetrachloride solution that is easily prepared by stirring an aqueous solution of sodium periodate NaIO4 with a suspension of hydrated ruthenium dioxide in CCl4. Ruthenium tetroxide partitions between CCl4 and water, resulting in a 60:1 concentration ratio.
Production Methods
Ruthenium(VIII) oxide (ruthenium tetraoxide) RuO4 is formed when an alkaline ruthenium solution is treated with a strong oxidant, such as chlorine, or bromate ion when the Ru is in acid solution.
Toxicity evaluation
Ruthenium tetroxide(RuO4) is a toxic and explosive compound, and, although it is less toxic than OsO4, it must be handled in a well ventilated fume hood using goggles and gloves. It can be destroyed with a sodium bisulfite solution, resulting in the much safer and less toxic ruthenium dioxide, which is a dark insoluble solid with very low vapor pressure.
