potassium carbonate in acetone T=56°C; 21 h;

potassium carbonate in acetonitrile Heating;

1: 23 percent / Br2 / CH2Cl2 / 15 h / 0 °C 2: 1.) n-BuLi, 2.) 1percent aq. HCl / 1.) THF, hexane, -78 deg C, 25 min, 2.) THF, hexane, CH2Cl2 3: 90 percent / K2CO3 / acetone / 21 h / 56 °C View Scheme

1: 1.) n-BuLi, 2.) 1percent aq. HCl / 1.) THF, hexane, -78 deg C, 25 min, 2.) THF, hexane, CH2Cl2 2: 90 percent / K2CO3 / acetone / 21 h / 56 °C View Scheme