1: 1.6 g / hydrogen chloride(gas), conc. hydrogen chloride / dioxane / 2 h / 50 - 60 °C 2: 0.5 g / selenium dioxide / xylene / 6 h / Heating 3: 1.) N-bromosuccinimide, benzoyl peroxide; 2.) triethylamine / 1.) carbon tetrachloride, irradiation, reflux, 2 h; 2.) reflux, 8 h View Scheme