carbon tetrabromide; triphenylphosphine in dichloromethane T=-5°C;

1: 1.) EtMgBr / 1.) THF 2: 1.) EtMgBr / 1.) THF, 30 min, 0 deg C 2.) THF, -35 deg C, 1 h; RT, 2 h 3: 85 percent / H2 / P-2-Ni 4: 88 percent / CBr4; PPh3 / CH2Cl2 / 24 h / Ambient temperature View Scheme

1: 1.) EtMgBr / 1.) THF, 30 min, 0 deg C 2.) THF, -35 deg C, 1 h; RT, 2 h 2: 85 percent / H2 / P-2-Ni 3: 88 percent / CBr4; PPh3 / CH2Cl2 / 24 h / Ambient temperature View Scheme

1: 85 percent / H2 / P-2-Ni 2: 88 percent / CBr4; PPh3 / CH2Cl2 / 24 h / Ambient temperature View Scheme

2: 0.1 M aq. p-toluenesulfonic acid / tetrahydrofuran / 0.3 h / Heating 3: 1.) NaN(SiMe3)2 / 1.) THF, toluene, r.t., 1 h 2.) THF, -100 deg C to 0 deg C 4: 0.1 M aq. p-toluenesulfonic acid / tetrahydrofuran / 0.3 h / Heating 5: 1.) LiAlH4 2.) 2N HCl, H2O / 1.) THF, -70 deg C 2.) -20 deg C 6: 95 percent / CBr4, triphenylphosphine / CH2Cl2 / -5 °C View Scheme

1: 1.) LiAlH4 2.) 2N HCl, H2O / 1.) THF, -70 deg C 2.) -20 deg C 2: 95 percent / CBr4, triphenylphosphine / CH2Cl2 / -5 °C View Scheme

1: 1.) NaN(SiMe3)2 / 1.) THF, toluene, r.t., 1 h 2.) THF, -100 deg C to 0 deg C 2: 0.1 M aq. p-toluenesulfonic acid / tetrahydrofuran / 0.3 h / Heating 3: 1.) LiAlH4 2.) 2N HCl, H2O / 1.) THF, -70 deg C 2.) -20 deg C 4: 95 percent / CBr4, triphenylphosphine / CH2Cl2 / -5 °C View Scheme

1: 0.1 M aq. p-toluenesulfonic acid / tetrahydrofuran / 0.3 h / Heating 2: 1.) NaN(SiMe3)2 / 1.) THF, toluene, r.t., 1 h 2.) THF, -100 deg C to 0 deg C 3: 0.1 M aq. p-toluenesulfonic acid / tetrahydrofuran / 0.3 h / Heating 4: 1.) LiAlH4 2.) 2N HCl, H2O / 1.) THF, -70 deg C 2.) -20 deg C 5: 95 percent / CBr4, triphenylphosphine / CH2Cl2 / -5 °C View Scheme

1: 0.1 M aq. p-toluenesulfonic acid / tetrahydrofuran / 0.3 h / Heating 2: 1.) LiAlH4 2.) 2N HCl, H2O / 1.) THF, -70 deg C 2.) -20 deg C 3: 95 percent / CBr4, triphenylphosphine / CH2Cl2 / -5 °C View Scheme

1: 75 percent / CuCl 2: 82 percent / H2 / Lindlar catalyst 3: 43 percent / PPh3Br2 View Scheme