hydrogenchloride in acetone T=5 - 20°C; 0.333333 h;

n-butyllithium; boron trifluoride diethyl etherate T=-78°C; 1) THF - hexane, 1 h, then 15 min, 2) 15 min;

1: 83 percent / toluene / 4 h / Heating 2: 90 percent / n-BuLi / tetrahydrofuran; cyclohexane / 1.) -78 deg C, 2 min, 2.) -78 deg C, 2-5 min 3: 92 percent / aq. HCl / acetone / 0.33 h / 5 - 20 °C View Scheme

1: 90 percent / n-BuLi / tetrahydrofuran; cyclohexane / 1.) -78 deg C, 2 min, 2.) -78 deg C, 2-5 min 2: 92 percent / aq. HCl / acetone / 0.33 h / 5 - 20 °C View Scheme