1: 80 percent / CrO3, AcOH / 1 h / Ambient temperature 2: 70 percent / NaBH4, CeCl3*7H2O / methanol / 0.5 h 3: 85 percent / pyridine / Ambient temperature 4: 60 percent / Et3N / 12 h / Heating 5: 93 percent / H2 / 10percent Pd/C / methanol / 5 h / Ambient temperature View Scheme