sodium iodide in acetonitrile T=0°C;

sodium iodide in acetone 32 h; Reflux;

chloro-trimethyl-silane; sodium iodide

1: Ce(SO4)2/silica gel 2: 67.9 g / PPh3; I2; imidazole / CH2Cl2 / 0.17 h / 20 °C View Scheme

1: 79 percent / 1.) Mg, 1,2-dibromoethane; 2.) CuBr; 3.) 45percent aq. NaOH / 1.) THF, reflux, 1 h; 2.) THF, -30 deg C, 90 min then -10 deg C, 90 min; 3.) EtOH, 3 h, rt. 2: 91 percent / Br2 / CCl4 / 2 h / 0 °C 3: 1.) KOH; 2.) BuBr, Mg, i-Pr2NH / 1.) EtOH, reflux, 16 h; 2.) THF, refluxed, 4 h View Scheme