1: 2) HBr / 1) pentane, 0 deg C, 1 h, 2) Et2O, 0 deg C 2: 70 percent / acetonitrile / 3 h / Ambient temperature 3: 78 percent / toluene / 0.5 h / Heating View Scheme

1: 96 percent / NEt3 / CH2Cl2 / 1 h / 0 °C 2: 78 percent / toluene / 0.5 h / Heating View Scheme

in toluene 0.5 h; Heating;