1: 1.) 98 percent formic acid, 2.) NaBH3(CN) / 1.) 38 deg C, 1 h, 2.) 20 deg C, 2 h 2: 83 percent / ethanol / 16 h / 78 °C 3: 75 percent / LiAlH4 / tetrahydrofuran / 3 h / Heating 4: 83 percent / 48 percent aq. HBr / 18 h / 120 °C View Scheme