1: 23 percent / SnCl4 / CH2Cl2 / 2 h / Ambient temperature 2: 96 percent / LiAlH4, AlCl3 / diethyl ether / 1 h / Heating 3: 75 percent / iodine / toluene / 48 h / Heating 4: 8 percent / Nafion-H / toluene / 24 h / Heating View Scheme

iodine in toluene 48 h; Heating;

bromine; iron in tetrachloromethane 4 h; Ambient temperature;