sodium hydroxide in 1,4-dioxane; water T=20°C; 17 h;

hydrogenchloride; sodium cyanoborohydride in methanol T=20°C; 24 h;

1: 90 percent / DIEA / dimethylformamide / 4 h / 20 °C 2: 87 percent / pyridine / ethanol / 2 h / Heating 3: 80 percent / BH3*THF / tetrahydrofuran / 3.5 h / Heating 4: 75 percent / sodium cyanoborohydride; HCl / methanol / 24 h / 20 °C View Scheme

1: 90 percent / DIEA / dimethylformamide / 4 h / 20 °C 2: 87 percent / pyridine / ethanol / 2 h / Heating 3: 80 percent / BH3*THF / tetrahydrofuran / 3.5 h / Heating 4: 75 percent / sodium cyanoborohydride; HCl / methanol / 24 h / 20 °C View Scheme

1: 87 percent / pyridine / ethanol / 2 h / Heating 2: 80 percent / BH3*THF / tetrahydrofuran / 3.5 h / Heating 3: 75 percent / sodium cyanoborohydride; HCl / methanol / 24 h / 20 °C View Scheme

1: 80 percent / BH3*THF / tetrahydrofuran / 3.5 h / Heating 2: 75 percent / sodium cyanoborohydride; HCl / methanol / 24 h / 20 °C View Scheme

1.1: 90 percent / NaI / 1,2-dimethoxy-ethane / 11 h 2.1: BuLi / hexane; tetrahydrofuran / 0.42 h / 0 °C 2.2: hexane; tetrahydrofuran / 13 h 2.3: 235 mg / NaBH4 / methanol; ethyl acetate / 1.25 h / 0 °C 3.1: Me3SiBr / CH2Cl2 / 0.5 h / 0 °C 4.1: 224 mg / CH2Cl2 / 3 h 5.1: 91 percent / aq. NaOH / dioxane / 4 h View Scheme

1.1: BuLi / hexane; tetrahydrofuran / 0.42 h / 0 °C 1.2: hexane; tetrahydrofuran / 13 h 1.3: 235 mg / NaBH4 / methanol; ethyl acetate / 1.25 h / 0 °C 2.1: Me3SiBr / CH2Cl2 / 0.5 h / 0 °C 3.1: 224 mg / CH2Cl2 / 3 h 4.1: 91 percent / aq. NaOH / dioxane / 4 h View Scheme

1: Me3SiBr / CH2Cl2 / 0.5 h / 0 °C 2: 224 mg / CH2Cl2 / 3 h 3: 91 percent / aq. NaOH / dioxane / 4 h View Scheme

1: HF; anisole / 1 h / 0 °C 2: 505 mg / NaOH / H2O; ethanol / 1 h / 20 °C View Scheme