1: 1-iodo-4-decyne With iodine; magnesium in diethyl ether Heating; 2: pentylpentylketone in diethyl ether T=0°C;

1: 1.) n-BuLi / 1.) THF, hexane, from -20 deg C to RT, 20 min, 2.) THF, hexane, from -78 deg C to RT 2: 1.) n-BuLi / 1.) THF, hexane, 2.) THF, hexane, from -78 deg C to RT 3: CuCl2/SiO2 / CH2Cl2 / 48 h / Ambient temperature View Scheme