aluminum oxide; potassium hydroxide; dibromo-difluoro-methane in dichloromethane T=20°C; 1 h;

1: 1.) Zn, PPh3 / 1.) 20 deg C, 72 h, 2.) CH2Cl2, from 0 deg C to RT, 2.5 h 2: 72.5 percent / Et3N, HPO(OEt)2 / 17 h / 50 °C 3: 87 percent / Pd(PPh3)4 / tetrahydrofuran / 8 h / 0 °C 4: aq. KF / dimethylformamide / 5 h / Ambient temperature 5: 1.) bis(cyclopentadienyl)zirconium chloride hydride, 2.) PdCl2(PPh3)2, DIBAH / 1.) benzene, RT, 0.5 h, 2.) benzene, hexane, THF, RT, 16 h View Scheme

1: 87 percent / Pd(PPh3)4 / tetrahydrofuran / 8 h / 0 °C 2: aq. KF / dimethylformamide / 5 h / Ambient temperature 3: 1.) bis(cyclopentadienyl)zirconium chloride hydride, 2.) PdCl2(PPh3)2, DIBAH / 1.) benzene, RT, 0.5 h, 2.) benzene, hexane, THF, RT, 16 h View Scheme

1: 72.5 percent / Et3N, HPO(OEt)2 / 17 h / 50 °C 2: 87 percent / Pd(PPh3)4 / tetrahydrofuran / 8 h / 0 °C 3: aq. KF / dimethylformamide / 5 h / Ambient temperature 4: 1.) bis(cyclopentadienyl)zirconium chloride hydride, 2.) PdCl2(PPh3)2, DIBAH / 1.) benzene, RT, 0.5 h, 2.) benzene, hexane, THF, RT, 16 h View Scheme

1: aq. KF / dimethylformamide / 5 h / Ambient temperature 2: 1.) bis(cyclopentadienyl)zirconium chloride hydride, 2.) PdCl2(PPh3)2, DIBAH / 1.) benzene, RT, 0.5 h, 2.) benzene, hexane, THF, RT, 16 h View Scheme

1: 44 percent / oxone / methanol; H2O / 0 °C 2: 35 percent / KOH; Al2O3; CBr2F2 / CH2Cl2 / 1 h / 20 °C View Scheme

bis-triphenylphosphine-palladium(II) chloride; Schwartz's reagent; diisobutylaluminium hydride 1.) benzene, RT, 0.5 h, 2.) benzene, hexane, THF, RT, 16 h; Yield given. Multistep reaction;