in acetic anhydride T=50°C; 0.5 h;

1: 66 percent / acetic anhydride / 0.5 h / 50 °C 2: 58 percent / NaBH4, CeCl3*7H2O / methanol / 0 - 5 °C 3: 38 percent / (+)-diisopropyl L-tartrate, Ti(O-i-Pr)4, t-butyl hydroperoxide / CH2Cl2; various solvent(s) / 15 h / -20 °C 4: 98 percent / PCC / CH2Cl2 / 18 h / Ambient temperature 5: NaH / dimethylformamide / 4 h / 60 °C View Scheme

1: 66 percent / acetic anhydride / 0.5 h / 50 °C 2: 88 percent / 30percent aq. H2O2, 20percent aq. NaOH / dimethylformamide / 0.5 h / Ambient temperature 3: 1.) NaH / 1.) DMF, RT, 5 min, 2.) DMF, 50 deg C, 17 h 4: 64 percent / NaBH4 / ethanol / 1 h / Ambient temperature 5: 64 percent / CH2Cl2 / 1 h / Heating View Scheme

Multi-step reaction with 2 steps 1: 66 percent / acetic anhydride / 0.5 h / 50 °C2: 58 percent / NaBH4, CeCl3*7H2O / methanol / 0 - 5 °C