1: 35 percent / CHCl3 / 0.5 h / Ambient temperature 2: 42 percent / P2O5 / 21 h / 60 - 70 °C 3: 80 percent / BH3 / tetrahydrofuran / 4 h / Heating 4: 100 percent / KOH / H2O; ethanol / 1 h / Heating 5: 55 percent / 5percent Pd/C / acetic acid / 24 h / Heating View Scheme