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

1: TBAF / tetrahydrofuran / Ambient temperature 2: Dess-Martin reagent / CH2Cl2 / 0 °C 3: 53 percent / Ni(acac)2, PPh3, DIBAL-H, 1,3-cyclohexadiene / tetrahydrofuran / 15 h / Ambient temperature 4: 95 percent / pyridine; CH2Cl2 / Ambient temperature 5: DOWEX 50WX8 / methanol / 50 °C 6: Et3N / CH2Cl2 7: PPTS / CH2Cl2 / Ambient temperature 8: TBAF / tetrahydrofuran / Ambient temperature 9: PCC, 4 Angstroem molecular sieves, NaOAc / CH2Cl2 / 0 °C 10: NaH / tetrahydrofuran / Ambient temperature 11: 92 percent / (S)-binaphthol, LiAlH4 / ethanol; tetrahydrofuran / -100 - -78 °C 12: 93 percent / acetic acid / H2O; tetrahydrofuran / 40 °C 13: 95 percent / 1N NaOH / methanol; tetrahydrofuran / Ambient temperature View Scheme

acetic acid T=40 - 45°C; 2 h;

1: diisobutylaluminium 2,6-t-butyl-4-methylphenyl / toluene / 2.5 h / -78 - -10 °C 2: aq. AcOH / 2 h / 40 - 45 °C View Scheme

1: diethyl ether / 0.5 h / 0 - 5 °C 2: imidazole / dimethylformamide / 2 h / Ambient temperature 3: 95 percent / 30percent hydrogen peroxide, 3 M aq. lithium hydroxide / methanol / 5 h / -30 - -25 °C 4: aq. sodium hydrogen carbonate, aluminium amalgam / tetrahydrofuran; methanol / 1.) 10 deg C, 2 h, 2.) room temperature, 4 h 5: 80 percent / K-Selectride / tetrahydrofuran / 5 h / -50 - -45 °C 6: hydrofluoric acid / acetonitrile / 1 h / -5 °C View Scheme

1: imidazole / dimethylformamide / 2 h / Ambient temperature 2: 95 percent / 30percent hydrogen peroxide, 3 M aq. lithium hydroxide / methanol / 5 h / -30 - -25 °C 3: aq. sodium hydrogen carbonate, aluminium amalgam / tetrahydrofuran; methanol / 1.) 10 deg C, 2 h, 2.) room temperature, 4 h 4: 80 percent / K-Selectride / tetrahydrofuran / 5 h / -50 - -45 °C 5: hydrofluoric acid / acetonitrile / 1 h / -5 °C View Scheme

1: 95 percent / 30percent hydrogen peroxide, 3 M aq. lithium hydroxide / methanol / 5 h / -30 - -25 °C 2: aq. sodium hydrogen carbonate, aluminium amalgam / tetrahydrofuran; methanol / 1.) 10 deg C, 2 h, 2.) room temperature, 4 h 3: 80 percent / K-Selectride / tetrahydrofuran / 5 h / -50 - -45 °C 4: hydrofluoric acid / acetonitrile / 1 h / -5 °C View Scheme

1: 80 percent / K-Selectride / tetrahydrofuran / 5 h / -50 - -45 °C 2: hydrofluoric acid / acetonitrile / 1 h / -5 °C View Scheme

1: aq. sodium hydrogen carbonate, aluminium amalgam / tetrahydrofuran; methanol / 1.) 10 deg C, 2 h, 2.) room temperature, 4 h 2: 80 percent / K-Selectride / tetrahydrofuran / 5 h / -50 - -45 °C 3: hydrofluoric acid / acetonitrile / 1 h / -5 °C View Scheme

1.1: 1H-imidazole / N,N-dimethyl-formamide / 18 h / 25 °C 2.1: hydrogen fluoride / water / 0.08 h / 25 °C 3.1: chromium(VI) oxide / acetone / 4 °C 3.2: 4 h / 25 °C View Scheme