1: With sulfuric acid; bromine; acetic acid in water T=20°C; 20 h; 2: With sodium hydrogencarbonate in water

1.1: phosphorus oxytribromide / acetonitrile / 20 °C / Reflux 2.1: tetrabutylammomium bromide / toluene / 10 h / Reflux 3.1: hydrogen / palladium 10 on activated carbon / ethyl acetate / 18 h / Inert atmosphere 4.1: hydrogenchloride; water / 24 h / Reflux 5.1: sulfuric acid / 48 h / Reflux 5.2: 20 °C 6.1: bromine; sulfuric acid; acetic acid / water / 20 h / 20 °C View Scheme

1.1: hydrogen / palladium 10 on activated carbon / ethyl acetate / 18 h / Inert atmosphere 2.1: hydrogenchloride; water / 24 h / Reflux 3.1: sulfuric acid / 48 h / Reflux 3.2: 20 °C 4.1: bromine; sulfuric acid; acetic acid / water / 20 h / 20 °C View Scheme

1.1: tetrabutylammomium bromide / toluene / 10 h / Reflux 2.1: hydrogen / palladium 10 on activated carbon / ethyl acetate / 18 h / Inert atmosphere 3.1: hydrogenchloride; water / 24 h / Reflux 4.1: sulfuric acid / 48 h / Reflux 4.2: 20 °C 5.1: bromine; sulfuric acid; acetic acid / water / 20 h / 20 °C View Scheme