bromine in tetrachloromethane T=20°C; 2 h;

potassium hydroxide in ethanol Heating;

1: 62 percent / K2CO3 / acetone / 72 h / Heating 2: 82 percent / Br2 / CCl4 / 2 h / 20 °C View Scheme

1: 67.2 percent / K2CO3 / dimethylformamide / 24 h / 80 °C 2: 92.8 percent / Br2 / CCl4 / 5 °C View Scheme

in water; dimethyl sulfoxide

1: Br2; HBr 2: KOH / ethanol / Heating View Scheme

1: sodium hydroxide / benzene / 20 h / 20 °C 2: 0.5 h / 200 °C / neat (no solvent, solid phase) 3: bromine; sodium sulfite / chloroform; water / 0 - 20 °C / Inert atmosphere View Scheme

1.1: n-butyllithium / tetrahydrofuran / 0.33 h / -78 °C / Inert atmosphere 1.2: 24 h / -78 - 20 °C / Inert atmosphere 1.3: 0.33 h / 0 °C 2.1: sodium hydroxide / benzene / 20 h / 20 °C 3.1: 0.5 h / 200 °C / neat (no solvent, solid phase) 4.1: bromine; sodium sulfite / chloroform; water / 0 - 20 °C / Inert atmosphere View Scheme

1: 1,4-dibromo-2,5-bis(hexyloxy)-benzene With n-butyllithium in diethyl ether; hexane 1 h; Heating; 2: N,N-dimethyl-formamide T=0 - 20°C;

1: 1,4-dibromo-2,5-bis(hexyloxy)-benzene With n-butyllithium in diethyl ether; n-heptane T=-20 - 20°C; 2: N,N-dimethyl-formamide in diethyl ether T=20°C; Bouveault reaction; 1 h; Further stages.;