1: 86 percent / 20 percent methanolic KOH / 4 h / Heating 2: 36 percent / HgO/Br2, CH2Br2 / 1 h / 60 - 80 °C 3: 85 percent / 50 percent H2SO4 / diethyl ether / 6 h / Ambient temperature 4: 86 percent / 1 N LiOH / 6 h / 80 °C View Scheme