n-butyllithium in hexane; pentane byproducts: LiCl; dropwise addn. of soln. of BuLi (hexane, 1 equiv.) to soln. of bromonaphthalene (pentane) at -30°C, stirring for 80 min, addn. of soln. of BCl3 (hexane, 1/3 equiv.) at -40°C, stirring at room temp. overnight; evapn., sublimation off of byproducts (150°C, 0.05 Torr), sublimation (220°C, 0.05 Torr or 150°C, 1E-5 Torr); elem. anal.;

chlorosulfonic acid; bromine

1: 0.13 g / dimethylformamide / 4 h / Heating 2: BuLi / diethyl ether; hexane / 2 h / -75 °C 3: 0.24 g / Br2 / diethyl ether / 1.) -75 deg C, 1 h, 2.) room temperature, 1 h View Scheme

hydrogen fluoride; copper(I) bromide; sodium nitrite 1) -20 to 0 deg. C, 2 h and 0 deg. C, 4 h; 2) 48percent HBr, 60 deg. C; Yield given. Multistep reaction;

magnesium; ethylene dibromide 1) Et2O, 1h, reflux 2) 1h, reflux; Yield given. Multistep reaction;