1: 89 percent / tetrahydrofuran / -78 °C 2: 91 percent / p-TosOH, H2O / acetone 3: 87 percent / NaBH4, CeCl3*7H2O / methanol 4: 60 percent / PPh3, Diethylazodicarboxylat (DEAD) / tetrahydrofuran 5: 85 percent / NH3 / methanol / sealed tube 6: 85 percent / HCl / methanol View Scheme

Multi-step reaction with 2 steps 1: 89 percent / tetrahydrofuran / -78 °C2: 91 percent / p-TosOH, H2O / acetone