1: pyridine / CH2Cl2 / 0.5 h / 0 °C 2: aq. OsO4, Me3NO / acetone; 2-methyl-propan-2-ol / 48 h 3: 58 percent / benzene / 1 h / Ambient temperature 4: 91 percent / K2CO3 / methanol / 2 h / 60 °C 5: 69 percent / H2 / 10percent Pd/C / methanol / 24 h View Scheme