1: 82 percent / 2,6-lutidine / CH2Cl2 2: 14 percent / CeCl3*7H2O, NaBH4 / methanol / 1.67 h / -60 - 0 °C 3: DMAP, pyridine / CH2Cl2 / 12 h / Ambient temperature 4: pyridine*HF / tetrahydrofuran / 1 h / Ambient temperature 5: Dess-Martin periodinane / 0.67 h / Ambient temperature 6: tetrahydrofuran / 1 h / -80 - -47 °C 7: Dess-Martin periodinane / CH2Cl2 / 0.42 h / Ambient temperature 8: pyridine, CSA / CH2Cl2 / 1 h / Ambient temperature 9: 88 percent / K2CO3 / methanol / 60 h / Ambient temperature 10: 90 percent / 2,6-lutidine / CH2Cl2 11: 1.) dicyclohexylmagnesium bromide / 1.) THF, -65 to -50 deg C, 35 min, 2.) THF, -65 to -50 deg C, 40 min 12: 93 percent / TBAF / tetrahydrofuran / 34 h / Ambient temperature 13: 3 Angstroem molecular sieves, TFA / CH2Cl2 / 0.6 h / Ambient temperature View Scheme