1: NEt3 / CH2Cl2 / 0.5 h / 0 °C 2: NaI / acetone / 10 h / Heating 3: Li2CuCl4 / tetrahydrofuran / 0.5 h / 25 °C 4: pyridinium p-toluenesulfonate / ethanol / 3.5 h / 40 °C 5: 1.) sodium hydride / 1.) DME, 50 deg C to 55 deg C, 2 h, 2.) toluene, -10 deg C, 2 h 6: 1.) n-BuLi / 1.) THF, hexane, -78 deg C, 0.5 h, 2.) -78 deg C, 2 h View Scheme

1: Li2CuCl4 / tetrahydrofuran / 0.5 h / 25 °C 2: pyridinium p-toluenesulfonate / ethanol / 3.5 h / 40 °C 3: 1.) sodium hydride / 1.) DME, 50 deg C to 55 deg C, 2 h, 2.) toluene, -10 deg C, 2 h 4: 1.) n-BuLi / 1.) THF, hexane, -78 deg C, 0.5 h, 2.) -78 deg C, 2 h View Scheme

1: 64 percent / conc. aq. HCl / 0.5 h / 0 - 5 °C 2: NEt3 / CH2Cl2 / 0.5 h / 0 °C 3: NaI / acetone / 10 h / Heating 4: Li2CuCl4 / tetrahydrofuran / 0.5 h / 25 °C 5: pyridinium p-toluenesulfonate / ethanol / 3.5 h / 40 °C 6: 1.) sodium hydride / 1.) DME, 50 deg C to 55 deg C, 2 h, 2.) toluene, -10 deg C, 2 h 7: 1.) n-BuLi / 1.) THF, hexane, -78 deg C, 0.5 h, 2.) -78 deg C, 2 h View Scheme

1: NaI / acetone / 10 h / Heating 2: Li2CuCl4 / tetrahydrofuran / 0.5 h / 25 °C 3: pyridinium p-toluenesulfonate / ethanol / 3.5 h / 40 °C 4: 1.) sodium hydride / 1.) DME, 50 deg C to 55 deg C, 2 h, 2.) toluene, -10 deg C, 2 h 5: 1.) n-BuLi / 1.) THF, hexane, -78 deg C, 0.5 h, 2.) -78 deg C, 2 h View Scheme

n-butyllithium Yield given. Multistep reaction;