bromine in acetic acid T=50°C; 0.5 h;

sodium hydroxide in acetic acid

n-butyllithium in tetrahydrofuran; hexane T=-19°C; Dehalogenation; 4.5 h;

bromine in acetic acid T=20°C; Bromination; 5 h;

1: 97 percent / Et3SiH / trifluoroacetic acid / 3 h / 60 °C 2: 65 percent / H2O2 / Na2WO4*2H2O / methanol; H2O / 0.5 h / 20 °C 3: 94 percent / BF3 / 0.67 h / Heating 4: 99 percent / aq. NaOH / methanol / 4 h / Heating 5: 92 percent / pyridine / 0.67 h / 20 °C 6: 28 percent / Br2 / acetic acid / 5 h / 20 °C View Scheme

1: 65 percent / H2O2 / Na2WO4*2H2O / methanol; H2O / 0.5 h / 20 °C 2: 94 percent / BF3 / 0.67 h / Heating 3: 99 percent / aq. NaOH / methanol / 4 h / Heating 4: 92 percent / pyridine / 0.67 h / 20 °C 5: 28 percent / Br2 / acetic acid / 5 h / 20 °C View Scheme

1: 92 percent / pyridine / 0.67 h / 20 °C 2: 28 percent / Br2 / acetic acid / 5 h / 20 °C View Scheme

1: 94 percent / BF3 / 0.67 h / Heating 2: 99 percent / aq. NaOH / methanol / 4 h / Heating 3: 92 percent / pyridine / 0.67 h / 20 °C 4: 28 percent / Br2 / acetic acid / 5 h / 20 °C View Scheme

1: 99 percent / aq. NaOH / methanol / 4 h / Heating 2: 92 percent / pyridine / 0.67 h / 20 °C 3: 28 percent / Br2 / acetic acid / 5 h / 20 °C View Scheme