magnesium 1) Ether, 20 deg C, 2 h, 2) boiling, 2 h.; Yield given. Multistep reaction;

1: 77 percent / SF4 / 10 h / 45 - 50 °C 2: 79 percent / Chromic anhydride, sulfuric acid / acetic acid; acetic anhydride / 1 h / 40 °C 3: 74 percent / Sulfuric acid monohydrate / 10 h / Heating View Scheme

1: 77 percent / SF4 / 10 h / 45 - 50 °C 2: 79 percent / Chromic anhydride, sulfuric acid / acetic acid; acetic anhydride / 1 h / 40 °C 3: Thionyl chloride, pyridine / 10 h / Heating 4: Pyridine / CH2Cl2 / 2 h / 40 °C View Scheme