1: 10percent aq. HCl / tetrahydrofuran / 4 h / 50 °C 2: pyridinium chlorochromate, aluminum oxide / CH2Cl2 / 8 h / Ambient temperature 3: 30 percent / hydrofluoric acid / acetonitrile; H2O / 8 h / 45 °C View Scheme

Multi-step reaction with 3 steps 1: 42 percent / aluminum oxide / toluene / 0.5 h / Heating2: 77 percent / p-toluenesulfonic acid monohydrate / methanol / 12 h / Ambient temperature3: 75 percent / 1,3-dicyclohexylcarbodiimide, 4-(dimethylamino)pyridine / CH2Cl2 / 72 h / Ambient temperature  

Multi-step reaction with 5 steps 1: 89 percent / aluminum oxide / benzene / 0.25 h / Heating2: 94 percent / cerium(III) chloride heptahydrate, sodium borohydride / methanol / 0.17 h / Ambient temperature3: 42 percent / aluminum oxide / toluene / 0.5 h / Heating4: 77 percent / p-toluenesulfonic acid monohydrate / methanol / 12 h / Ambient temperature5: 75 percent / 1,3-dicyclohexylcarbodiimide, 4-(dimethylamino)pyridine / CH2Cl2 / 72 h / Ambient temperature  

Multi-step reaction with 2 steps 1: 10percent aq. HCl / tetrahydrofuran / 4 h / 50 °C2: pyridinium chlorochromate, aluminum oxide / CH2Cl2 / 8 h / Ambient temperature