acetic anhydride; acetic acid; zinc T=90°C; 4 h;

in diethyl ether; water

boron trifluoride diethyl etherate T=-100°C; 0.25 h;

1: 49.6 percent / SnBu3H / 10 h / 23 °C 2: 66 percent / Zn, AcOH, Ac2O / dimethylformamide / 6 h / 90 °C View Scheme

1: 86.5 percent / Bu3SnH / 3 h / Ambient temperature 2: 70 percent / Zn, AcOH, Ac2O / 4 h / 90 °C View Scheme

boron trifluoride diethyl etherate; tert.-butyl lithium 1) diethyl ether, pentane, -110 deg C, 0.5 h; 2) diethyl ether, pentane, -110 deg C, 10 min, -78 deg C, 1 h; Yield given. Multistep reaction;

1: pyridine / 6 h / 0 °C 2: dimethylsulfoxide / 1) 0 deg C, 20 min; 2) rt, 1.5-2 h 3: 55 percent / conc. HCl / 4.5 h / Heating 4: 85 percent / LiAlH4 / diethyl ether / 5 h / Ambient temperature 5: 1.) TsCl, pyridine, 2.) LiBr / 1) 0 deg C; 2) DMF, rt View Scheme