1: hydrobromic acid; acetic acid 2: potassium carbonate 3: borane-tetrahydrofuran complex / acetonitrile / 3 h / 20 °C 4: 85 percent / toluene / 20 h / Heating 5: 88 percent / borane-tetrahydrofuran complex / tetrahydrofuran / 3 h / 20 °C 6: 90 percent / hydrogen / Pd/C / methanol / 2 h / 20 °C / 760 Torr View Scheme