1: aq. HCl / CHCl3 / 3 h 2: 0.761 g / NaBH4 / methanol / 1 h 3: ammonium formate / Pd/C / methanol / 0.5 h / Heating 4: 0.702 g / CH2Cl2 / 2 h / 20 °C 5: Et3N / tetrahydrofuran / 0.17 h / 20 °C 6: KOt-Bu / tetrahydrofuran / 0.5 h / 0 °C 7: 0.327 g / TBAF / tetrahydrofuran / 12 h 8: Et3N / CH2Cl2 / 0.17 h / 20 °C 9: 0.127 g / NaH / dimethylformamide / 0.25 h / Heating 10: TFA / CH2Cl2 / 1.5 h View Scheme

1: aq. HCl / CHCl3 / 3 h 2: 0.761 g / NaBH4 / methanol / 1 h 3: ammonium formate / Pd/C / methanol / 0.5 h / Heating 4: 0.702 g / CH2Cl2 / 2 h / 20 °C 5: Et3N / tetrahydrofuran / 0.17 h / 20 °C 6: KOt-Bu / tetrahydrofuran / 0.5 h / 0 °C 7: 0.327 g / TBAF / tetrahydrofuran / 12 h View Scheme