N-bromosuccinmide in dichloromethane T=10°C; 2 h;

1: 84 percent / N-bromo succinimide / CH2Cl2 / 2 h / 10 °C 2: 1) n-Bu3SnH, azobisisobutyronitrile, 2) toluene-p-sulfonic acid / 1) benzene, 80 deg C, 1.5 h, 2) benzene, room temp., 15 min View Scheme