1: Et3N / CH2Cl2 / 1 h / 0 °C 2: 79 percent / Dibal / toluene / 2 h / 0 °C 3: 100 percent / MsCl, Et3N / CH2Cl2 / 18 h / 0 - 20 °C 4: 100 percent / HCO2H / Pd black / methanol / 18 h / Ambient temperature 5: 84 percent / Dowex 50W-X8 / methanol / 24 h View Scheme