1: 2,6-dibromohex-1-ene With magnesium; ethylene dibromide in tetrahydrofuran T=10 - 20°C; 4 h; 2: phenyl-trichloro-silane in tetrahydrofuran 1.4 h; Heating;

1.1: Speier's catalyst 2.1: magnesium; 1,2-dibromoethane / tetrahydrofuran / 4 h / 10 - 20 °C 2.2: 53 percent / tetrahydrofuran / 1.4 h / Heating View Scheme

1.1: bromine / diethyl ether / 20 °C 2.1: potassium hydroxide / diethyl ether / Heating 2.2: NEt3 / CH2Cl2 / 20 °C 2.3: LiBr / 1-methyl-pyrrolidin-2-one / 20 °C 3.1: magnesium; 1,2-dibromoethane / tetrahydrofuran / 4 h / 10 - 20 °C 3.2: 53 percent / tetrahydrofuran / 1.4 h / Heating View Scheme

1.1: potassium hydroxide / diethyl ether / Heating 1.2: NEt3 / CH2Cl2 / 20 °C 1.3: LiBr / 1-methyl-pyrrolidin-2-one / 20 °C 2.1: magnesium; 1,2-dibromoethane / tetrahydrofuran / 4 h / 10 - 20 °C 2.2: 53 percent / tetrahydrofuran / 1.4 h / Heating View Scheme