1: 1) BuLi, 2) ZnCl2, 3) PdCl2(PPh3)2, DIBAL-H / 1) THF, -78 deg C, 2) THF, -78 deg C, 3) THF, 0 deg C to RT 2: 72 percent / TiCl4 / CH2Cl2 / 16 h / Ambient temperature View Scheme

boron tribromide in dichloromethane Ambient temperature;

1: 1) BuLi, 2) ZnCl2, 3) PdCl2(PPh3)2, DIBAL-H / 1) THF, -78 deg C, 2) THF, -78 deg C, 3) THF, 0 deg C to RT 2: 95 percent / NaH / xylene / Heating 3: 89 percent / TFA / toluene / 1 h / Heating View Scheme