1: pyridine / CH2Cl2 / 0.5 h 2: NaN3 / dimethylformamide / 0.5 h / Ambient temperature 3: 93 percent / sodium borohydride / ethanol / 18 h / Ambient temperature 4: 94 percent / 4-dimethylaminopyridine, pyridine / 1) 0 deg C, 4 h, 2) 18 h, room temperature 5: 1) H2, 2) NaOAc / 1) 10percent palladium black / 1) EtOH, 2 h, room temperature, 2) 50 deg C, 12 h 6: 90 percent / 50percent aq. CF3CO2H / 6 h / Ambient temperature View Scheme