1: 95 percent / diisobutylaluminium hydride / toluene / -78 °C 2: 72 percent / CH2Cl2 3: 63 percent / barium oxide / toluene / Heating 4: Zn dust, AcOH / H2O / 70 °C 5: 2n Na2CO3 / tetrahydrofuran / 0 °C 6: 87 percent / barium hydroxide / H2O; dioxane / Heating 7: 68 percent / thionyl chloride 8: 76 percent / sodium borohydride / dimethylformamide / 80 °C 9: 85 percent / aqueous hydrobromic acid View Scheme