1: 86 percent / azobis(isobutyronitrile), Br2 / CCl4 / 3 h / 77 °C / Irradiation 2: 2) triethylamine / 1) THF; 2) THF, 1 h View Scheme

triethylamine 1) THF; 2) THF, 1 h; Yield given. Multistep reaction;