1: 66 percent / tetrahydrofuran / 0.5 h / -10 °C 3: NBS, NaHCO3 / hexane / 1 h / Heating 4: γ-collidine / xylene / 1.5 h / Heating 5: CH2Cl2 / 1 h / Ambient temperature 6: 48 percent / LiAlH4 / tetrahydrofuran / 1 h / Heating 7: ethanol / 0 °C / Irradiation 8: tetrahydrofuran / 1.5 h / Heating View Scheme

With  amberlyst-15 in  methanol 15 h;  Ambient temperature;   

Multi-step reaction with 4 steps 2: NaBH4 / ethanol / 2 h / Ambient temperature3: 66 percent / NaH / xylene / 20 h / Heating4: 78 percent / Amberlyst-15 / methanol / 15 h / Ambient temperature  

Multi-step reaction with 5 steps 1: 66 percent / tetrahydrofuran / 0.5 h / -10 °C3: NBS, NaHCO3 / hexane / 1 h / Heating4: γ-collidine / xylene / 1.5 h / Heating5: CH2Cl2 / 1 h / Ambient temperature  

Multi-step reaction with 6 steps 1: 66 percent / tetrahydrofuran / 0.5 h / -10 °C3: NBS, NaHCO3 / hexane / 1 h / Heating4: γ-collidine / xylene / 1.5 h / Heating5: CH2Cl2 / 1 h / Ambient temperature6: 48 percent / LiAlH4 / tetrahydrofuran / 1 h / Heating