carbon tetrabromide; triphenylphosphine in diethyl ether T=25°C; 0.5 h;

1: 1) n-BuLi / 1) Et2O, hexane, 0 deg C to room temperature; reflux, 24 h, 2) Et2O, hexane, -78 deg C to room temperature; room temperature, 2 h 2: 112.6 g / 10percent H2SO4 / diethyl ether; hexane View Scheme

borane in tetrahydrofuran 24 h; Ambient temperature;

1: NaBH4 / methanol 2: n-BuLi View Scheme

n-butyllithium 1.) 25 deg C, 24 h, 2.) 25 deg C, 1.5 h; Yield given. Multistep reaction. Further byproducts given;

1: di-isopropyl azodicarboxylate / tetrahydrofuran / 15 h / 20 °C 2: methanol / 1 h / UV-irradiation; Inert atmosphere View Scheme

1: 99 percent / pyridine / CH2Cl2 / 0 - 20 °C 2: 62 percent / DPPE-Pd(η3-C3H5)Cp / dimethylsulfoxide / 72 h / 120 °C View Scheme

1: 95 percent / PBr3 / diethyl ether / 2 h / Ambient temperature 2: 80 percent / various solvent(s) / 5.5 h / 80 - 100 °C 3: 1) n-BuLi, 2) HMPA / 1) THF, hexane, -78 deg C to room temperature, 2) THF, hexane, -78 deg C 4: 1) n-BuLi / 1) THF, hexane, -78 deg C to room temperature, 2) THF, hexane, -78 deg C to room temperature 5: TBAF, ethyl acrylate / acetonitrile / 0.83 h View Scheme

1: 99 percent / pyridine / CH2Cl2 / 0 - 20 °C 2: 42 percent / DPPE-Pd(η3-C3H5)Cp / dimethylsulfoxide / 72 h / 140 °C View Scheme