diphenyl diselenide; PhIO in toluene T=80°C; 9 h;

in hexane; methyl acetate; water

tetrapropylammonium perruthennate; 4 A molecular sieve; 4-methylmorpholine N-oxide in dichloromethane 0.5 h; Ambient temperature;

1: 94 percent / aq. NaOH / methanol / 1.5 h / Heating 2: 97 percent / tetra-n-propylammonium perruthenate, 4-methylmorpholine N-oxide, 4A molecular sieves / CH2Cl2 / 0.5 h / Ambient temperature View Scheme

1: 91 percent / Br2, HBr / acetic acid / 0.5 h / Ambient temperature 2: 66 percent / Li2CO3, LiBr / dimethylformamide / 16 h 3: 94 percent / aq. NaOH / methanol / 1.5 h / Heating 4: 97 percent / tetra-n-propylammonium perruthenate, 4-methylmorpholine N-oxide, 4A molecular sieves / CH2Cl2 / 0.5 h / Ambient temperature View Scheme

1: 66 percent / Li2CO3, LiBr / dimethylformamide / 16 h 2: 94 percent / aq. NaOH / methanol / 1.5 h / Heating 3: 97 percent / tetra-n-propylammonium perruthenate, 4-methylmorpholine N-oxide, 4A molecular sieves / CH2Cl2 / 0.5 h / Ambient temperature View Scheme