1: triethylamine / CH2Cl2 / 2 h / Ambient temperature 2: 70 percent / pyridine, bromine / CH2Cl2 / from -78 deg C to room temp. View Scheme

1: triethylamine / CH2Cl2 / 2 h / Ambient temperature 2: 70 percent / pyridine, bromine / CH2Cl2 / from -78 deg C to room temp. 3: 71 percent / sulphuryl chloride / CCl4 / Ambient temperature View Scheme

1: triethylamine / CH2Cl2 / 2 h / Ambient temperature 2: 70 percent / pyridine, bromine / CH2Cl2 / from -78 deg C to room temp. 3: 82 percent / diethyl ether / 0.5 h / from -78 deg C to room temp. 4: 60 percent / sulphuryl chloride 5: 82 percent / potassium amide / CH2Cl2; H2O / 0.5 h / from -78 deg C room temp. View Scheme