bromine; triethylamine; triphenylphosphine in dichloromethane a) 0.5 h, r.t., b) 12 h, r.t.;

1: 31 percent / xylene / 1 h / Heating 2: 61 percent / a) bromine, triphenylphosphine, b) Et3N / CH2Cl2 / a) 0.5 h, r.t., b) 12 h, r.t. View Scheme

1: 31 percent / xylene / 1 h / Heating 2: 61 percent / a) bromine, triphenylphosphine, b) Et3N / CH2Cl2 / a) 0.5 h, r.t., b) 12 h, r.t. View Scheme