chromium(VI) oxide in acetic acid 30-35 deg C, then r.t. 2 h;

1: Cl2 / -5 °C 2: diethyl ether / Ambient temperature; 6 h, then overnight 3: 67 percent / CrO3 / aq. acetic acid / 30-35 deg C, then r.t. 2 h View Scheme

1: diethyl ether / Ambient temperature; 6 h, then overnight 2: 67 percent / CrO3 / aq. acetic acid / 30-35 deg C, then r.t. 2 h View Scheme

1: 57 percent / NaH / dimethylformamide; diethyl ether / 6 h / Ambient temperature 2: 81 percent / LiAlH4 / diethyl ether / 3 h / Heating 3: 89 percent / aq. acetic acid / 1 h / Heating 4: Cl2 / -5 °C 5: diethyl ether / Ambient temperature; 6 h, then overnight 6: 67 percent / CrO3 / aq. acetic acid / 30-35 deg C, then r.t. 2 h View Scheme