pyridine; titanium tetrachloride 15 h; Heating;

1: 78 percent / Br2, pyridine / dimethylformamide 2: 54 percent / TiCl4 / pyridine / Heating View Scheme

1: 23 percent / benzene / 2.5 h / Heating 2: Br2, pyridine / dimethylformamide / 18 h / 100 - 110 °C 3: 54 percent / TiCl4, pyridine / 15 h / Heating View Scheme