1: With sodium acetate; iron in acetic acid 2: With bromine in acetic acid T=20°C; 1 h; Further stages.;

1: With bromine in tetrachloromethane T=20°C; 2: With water in tetrachloromethane T=0°C; Further stages.;

1.1: 2,4,4,6-tetrabromo-2,5-cyclohexadien-1-one / ethanol / 0.5 h / 40 °C / Inert atmosphere 2.1: sodium hydride / tetrahydrofuran / 1 h / 0 °C / Inert atmosphere 2.2: 0.67 h / 0 °C / Inert atmosphere 3.1: diethyl ether / 0.08 h / 0 °C / Inert atmosphere 4.1: potassium hexamethylsilazane / tetrahydrofuran / 2 h / -78 - 20 °C / Inert atmosphere 4.2: 0.5 h / 20 °C / Inert atmosphere 4.3: 12 h / 20 °C / Inert atmosphere View Scheme