sodium tert-pentoxide in toluene T=60 - 65°C; 3 h;

1: 60 percent / Mn; 2,4,6-collidine; Me3SiCl / Cp2TiCl2 / tetrahydrofuran / 20 °C 2: 76 percent / DMAP / CH2Cl2 / 2 h / 20 °C 3: 77 percent / AIBN; HSnBu3 / benzene / 1 h / Heating View Scheme

1: 68 percent / Li2CuCl4 / tetrahydrofuran / 0 - 20 °C 2: 60 percent / Mn; 2,4,6-collidine; Me3SiCl / Cp2TiCl2 / tetrahydrofuran / 20 °C 3: 76 percent / DMAP / CH2Cl2 / 2 h / 20 °C 4: 77 percent / AIBN; HSnBu3 / benzene / 1 h / Heating View Scheme

1: 68 percent / Li2CuCl4 / tetrahydrofuran / 0 - 20 °C 2: 60 percent / Mn; 2,4,6-collidine; Me3SiCl / Cp2TiCl2 / tetrahydrofuran / 20 °C 3: 76 percent / DMAP / CH2Cl2 / 2 h / 20 °C 4: 77 percent / AIBN; HSnBu3 / benzene / 1 h / Heating View Scheme

1: 1.) CuI, 2.) BF3*Et2O / 1.) Et2O, -25 deg C, 2.) Et2O, -30 deg C, 75 min 2: 1.) t-BuONa / 1.) PhMe, r.t., 20 min, 2.) PhMe, 60-65 deg C, 3 h View Scheme

sodium t-butanolate 1.) PhMe, r.t., 20 min, 2.) PhMe, 60-65 deg C, 3 h; Yield givenMultistep reaction;