1: (-)-(R)-3-(2-bromoethyl)cyclopentene With magnesium; ethylene dibromide in tetrahydrofuran 3.5 h; Heating; 2: 11-bromo-undecanoic acid With dilithium tetrachlorocuprate in tetrahydrofuran T=-20°C; Further stages.;

1.1: 82 percent / acetic acid; water; Zn / tetrahydrofuran / 2 h / 0 °C 2.1: 84 percent / LiAlH4 / tetrahydrofuran / 2.5 h / Heating 3.1: 88 percent / tetrabromomethane; triphenylphosphane / CH2Cl2 / 0 - 20 °C 4.1: Mg; 1,2-dibromoethane / tetrahydrofuran / 3.5 h / Heating 4.2: 58 percent / Li2CuCl4 / tetrahydrofuran / -20 °C View Scheme

1.1: 84 percent / LiAlH4 / tetrahydrofuran / 2.5 h / Heating 2.1: 88 percent / tetrabromomethane; triphenylphosphane / CH2Cl2 / 0 - 20 °C 3.1: Mg; 1,2-dibromoethane / tetrahydrofuran / 3.5 h / Heating 3.2: 58 percent / Li2CuCl4 / tetrahydrofuran / -20 °C View Scheme

1.1: (R)-4-tBu-2-[2-(2Bp-Ph-phosphanyl)-Cp]4,5diH-oxazole*Mn(CO)3; [(η3-C3H5)PdCl]2 / tetrahydrofuran / 0.25 h / 0 °C 1.2: 98 percent / tetrahydrofuran / 0.58 h / 0 °C 2.1: 91 percent / aq. NaOH / 4 h / Heating 3.1: 84 percent / LiAlH4 / tetrahydrofuran / 2.5 h / Heating 4.1: 88 percent / tetrabromomethane; triphenylphosphane / CH2Cl2 / 0 - 20 °C 5.1: Mg; 1,2-dibromoethane / tetrahydrofuran / 3.5 h / Heating 5.2: 58 percent / Li2CuCl4 / tetrahydrofuran / -20 °C View Scheme