N-bromosuccinmide in tetrahydrofuran T=-78 - 20°C; Inert atmosphereCooling with acetone-dry ice;

acetic acid T=60°C; 5 h; Inert atmosphere;

1: hydrogenchloride; SnCl2·2H2O / ethanol; water / 18 h / 20 °C 2: methanol / 2 h / 70 °C / Inert atmosphere 3: N-bromosuccinmide / tetrahydrofuran / -78 - 20 °C / Inert atmosphere; Cooling with acetone-dry ice View Scheme

1: methanol / 2 h / 70 °C / Inert atmosphere 2: N-bromosuccinmide / tetrahydrofuran / -78 - 20 °C / Inert atmosphere; Cooling with acetone-dry ice View Scheme

1: iron; acetic acid / 0.5 h / 60 °C 2: acetic acid / 5 h / 60 °C / Inert atmosphere View Scheme

1: 5,5''-dibromo-3',4'-dinitro-2,2':5'2''-terthiophene With iron; acetic acid T=60°C; 0.5 h; Inert atmosphere; 2: benzil T=60°C; 5 h; Inert atmosphere;