Me3NO in toluene under N2; Os complex in toluene treated with Me3NO at 60°C;

in toluene under N2; Os complex in toluene refluxed for 12 h; solvent removed under vac.; subjected to thin layer chromy. (silica gel,CS2-CH2Cl2-n-hexane 4:1:1); third green band collected; elem. anal.;