1.1: DMAP; pyridine / CH2Cl2 / 2 h / 20 °C 2.1: Dowex50W / methanol / 0.5 h / 50 °C 3.1: Et3N; DMAP / CH2Cl2 / 36 h / 20 °C 4.1: pyridinium p-toluenesulfonate / CH2Cl2 / 12 h / 20 °C 5.1: tetrabutylammonium fluoride / tetrahydrofuran / 16 h / 0 °C 6.1: PCC; 4 Angstroem molecular sieves / CH2Cl2 / 1 h / 0 °C 7.1: NaH / tetrahydrofuran / 0.08 h / 20 °C 7.2: tetrahydrofuran / 1 h 8.1: LiAlH4; (S)-binaphthol / tetrahydrofuran; ethanol / 1 h / -78 °C 9.1: aq. AcOH / tetrahydrofuran / 2.5 h / 40 °C 10.1: 1.0 M aq. NaOH / methanol; tetrahydrofuran / 2 h / 20 °C View Scheme

1: 95 percent / pyridine; CH2Cl2 / Ambient temperature 2: DOWEX 50WX8 / methanol / 50 °C 3: Et3N / CH2Cl2 4: PPTS / CH2Cl2 / Ambient temperature 5: TBAF / tetrahydrofuran / Ambient temperature 6: PCC, 4 Angstroem molecular sieves, NaOAc / CH2Cl2 / 0 °C 7: NaH / tetrahydrofuran / Ambient temperature 8: 92 percent / (S)-binaphthol, LiAlH4 / ethanol; tetrahydrofuran / -100 - -78 °C 9: 93 percent / acetic acid / H2O; tetrahydrofuran / 40 °C 10: 95 percent / 1N NaOH / methanol; tetrahydrofuran / Ambient temperature View Scheme