tetra(n-butyl)ammonium hydroxide in dichloromethane 16 h;

1: 48 percent / iron (III) sulphate on silica gel / hexane / 1.42 h / 45 °C 2: 84 percent / pyridine / CH2Cl2 / 16 h / Ambient temperature 3: 46 percent / I2, 1,2-bis(diphenylphosphino)ethane / CH2Cl2 / 4 h / Ambient temperature 4: 34 percent / dimethylsulfoxide / 2 h / Ambient temperature 5: 79 percent / trifluoroacetic acid, H2O / CH2Cl2 6: 1.) n-BuLi, 2.) HMPA / 1.) THF, hexane, 0 deg C, 10 min, 2.) THF, hexane, 0 deg C, 1.5 h 7: 88 percent / H2 / 10percent Pd/C / diethyl ether / 16 h 8: 44 percent / molecular sieves 4 A, pyridinum dichromate / dimethylformamide / 120 h / Ambient temperature 9: 94 percent / 10percent aq. tetrabutylammonium hydroxide / CH2Cl2 / 16 h View Scheme

1: 60 percent / I2, chlorodiphenylphosphine, imidazole / toluene / 3 h / 70 °C 2: 1.) n-BuLi, 2.) HMPA / 1.) THF, hexane, from -78 deg C to RT, 1 h, 2.) THF, hexane, form -78 deg C to RT, 4 h 3: 68 percent / methanolic para-toluenesulfonic acid / toluene / 144 h 4: 88 percent / H2 / 10percent Pd/C / diethyl ether / 16 h 5: 44 percent / molecular sieves 4 A, pyridinum dichromate / dimethylformamide / 120 h / Ambient temperature 6: 94 percent / 10percent aq. tetrabutylammonium hydroxide / CH2Cl2 / 16 h View Scheme

1: 91 percent / CH2Cl2 / 16 h / Ambient temperature 2: 77 percent / Na, liq. NH3 / tetrahydrofuran; ethanol / 3 h / -33 °C 3: 60 percent / I2, chlorodiphenylphosphine, imidazole / toluene / 3 h / 70 °C 4: 1.) n-BuLi, 2.) HMPA / 1.) THF, hexane, from -78 deg C to RT, 1 h, 2.) THF, hexane, form -78 deg C to RT, 4 h 5: 68 percent / methanolic para-toluenesulfonic acid / toluene / 144 h 6: 88 percent / H2 / 10percent Pd/C / diethyl ether / 16 h 7: 44 percent / molecular sieves 4 A, pyridinum dichromate / dimethylformamide / 120 h / Ambient temperature 8: 94 percent / 10percent aq. tetrabutylammonium hydroxide / CH2Cl2 / 16 h View Scheme

1: 77 percent / Na, liq. NH3 / tetrahydrofuran; ethanol / 3 h / -33 °C 2: 60 percent / I2, chlorodiphenylphosphine, imidazole / toluene / 3 h / 70 °C 3: 1.) n-BuLi, 2.) HMPA / 1.) THF, hexane, from -78 deg C to RT, 1 h, 2.) THF, hexane, form -78 deg C to RT, 4 h 4: 68 percent / methanolic para-toluenesulfonic acid / toluene / 144 h 5: 88 percent / H2 / 10percent Pd/C / diethyl ether / 16 h 6: 44 percent / molecular sieves 4 A, pyridinum dichromate / dimethylformamide / 120 h / Ambient temperature 7: 94 percent / 10percent aq. tetrabutylammonium hydroxide / CH2Cl2 / 16 h View Scheme

1: 84 percent / pyridine / CH2Cl2 / 16 h / Ambient temperature 2: 46 percent / I2, 1,2-bis(diphenylphosphino)ethane / CH2Cl2 / 4 h / Ambient temperature 3: 34 percent / dimethylsulfoxide / 2 h / Ambient temperature 4: 79 percent / trifluoroacetic acid, H2O / CH2Cl2 5: 1.) n-BuLi, 2.) HMPA / 1.) THF, hexane, 0 deg C, 10 min, 2.) THF, hexane, 0 deg C, 1.5 h 6: 88 percent / H2 / 10percent Pd/C / diethyl ether / 16 h 7: 44 percent / molecular sieves 4 A, pyridinum dichromate / dimethylformamide / 120 h / Ambient temperature 8: 94 percent / 10percent aq. tetrabutylammonium hydroxide / CH2Cl2 / 16 h View Scheme

1: 1.) n-BuLi, 2.) HMPA / 1.) THF, hexane, from -78 deg C to RT, 1 h, 2.) THF, hexane, form -78 deg C to RT, 4 h 2: 68 percent / methanolic para-toluenesulfonic acid / toluene / 144 h 3: 88 percent / H2 / 10percent Pd/C / diethyl ether / 16 h 4: 44 percent / molecular sieves 4 A, pyridinum dichromate / dimethylformamide / 120 h / Ambient temperature 5: 94 percent / 10percent aq. tetrabutylammonium hydroxide / CH2Cl2 / 16 h View Scheme

1: 65 percent / dimethylsulfoxide / 2 h / Ambient temperature 2: 1.) n-BuLi, 2.) HMPA / 1.) THF, hexane, from -78 deg C to RT, 1 h, 2.) THF, hexane, form -78 deg C to RT, 4 h 3: 68 percent / methanolic para-toluenesulfonic acid / toluene / 144 h 4: 88 percent / H2 / 10percent Pd/C / diethyl ether / 16 h 5: 44 percent / molecular sieves 4 A, pyridinum dichromate / dimethylformamide / 120 h / Ambient temperature 6: 94 percent / 10percent aq. tetrabutylammonium hydroxide / CH2Cl2 / 16 h View Scheme

1: 92 percent / para-toluenesulfonic acid / CH2Cl2 / 16 h / Ambient temperature 2: 65 percent / dimethylsulfoxide / 2 h / Ambient temperature 3: 1.) n-BuLi, 2.) HMPA / 1.) THF, hexane, from -78 deg C to RT, 1 h, 2.) THF, hexane, form -78 deg C to RT, 4 h 4: 68 percent / methanolic para-toluenesulfonic acid / toluene / 144 h 5: 88 percent / H2 / 10percent Pd/C / diethyl ether / 16 h 6: 44 percent / molecular sieves 4 A, pyridinum dichromate / dimethylformamide / 120 h / Ambient temperature 7: 94 percent / 10percent aq. tetrabutylammonium hydroxide / CH2Cl2 / 16 h View Scheme

1: 79 percent / trifluoroacetic acid, H2O / CH2Cl2 2: 1.) n-BuLi, 2.) HMPA / 1.) THF, hexane, 0 deg C, 10 min, 2.) THF, hexane, 0 deg C, 1.5 h 3: 88 percent / H2 / 10percent Pd/C / diethyl ether / 16 h 4: 44 percent / molecular sieves 4 A, pyridinum dichromate / dimethylformamide / 120 h / Ambient temperature 5: 94 percent / 10percent aq. tetrabutylammonium hydroxide / CH2Cl2 / 16 h View Scheme