silver hexafluoroantimonate; copper(I) bromide in 1,2-dichloro-ethane T=20°C; 0.5 h;

1: 94 percent / NaHCO3, NaCl / CHCl3; H2O / 1.5 h / Heating 2: 97 percent / NBS / CCl4 / 1 h / 20 °C / Irradiation 3: diisopropylethylamine / tetrahydrofuran / 0.25 h / -78 °C 4: tetrahydrofuran / 12 h / -78 deg C --> r.t. View Scheme

1: 94 percent / NaHCO3, NaCl / CHCl3; H2O / 1.5 h / Heating 2: 97 percent / NBS / CCl4 / 1 h / 20 °C / Irradiation 3: diisopropylethylamine / tetrahydrofuran / 0.25 h / -78 °C 4: tetrahydrofuran / 12 h / -78 deg C --> r.t. View Scheme

1: 97 percent / NBS / CCl4 / 1 h / 20 °C / Irradiation 2: diisopropylethylamine / tetrahydrofuran / 0.25 h / -78 °C 3: tetrahydrofuran / 12 h / -78 deg C --> r.t. View Scheme

pyridine; N-bromosuccinmide; molecular sieve; triphenylphosphine 1.) CH2Cl2, r.t., 30 min; 2.) r.t., 10.0 h; Yield given. Multistep reaction;