1: H2SO4 2: aq. NaOH / dioxane View Scheme

1: 58 percent / BH3*SMe2 / tetrahydrofuran / -15 - 20 °C 2: 90 percent / Et3N / CH2Cl2 / 4 h / -20 - 0 °C 3: 87 percent / NaN3 / dimethylformamide / 48 h / 20 °C 4: 79 percent / PPh3 / tetrahydrofuran / 6 h / 20 °C 5: 73 percent / H2; Et3N / Pd/C / methanol / 96 h / 20 °C View Scheme

1: 58 percent / BH3*SMe2 / tetrahydrofuran / -15 - 20 °C 2: 90 percent / Et3N / CH2Cl2 / 4 h / -20 - 0 °C 3: 87 percent / NaN3 / dimethylformamide / 48 h / 20 °C 4: 79 percent / PPh3 / tetrahydrofuran / 6 h / 20 °C View Scheme