1: 4.2 g / BuLi / hexane; tetrahydrofuran; hexamethylphosphoric acid triamide 2: 75 percent / TsOH / methanol / 2 h / Heating 3: 76 percent / Jones reagent / acetone / 0 °C 4: CF3COOH / 24 h / 20 °C View Scheme

1: 4.2 g / BuLi / hexane; tetrahydrofuran; hexamethylphosphoric acid triamide 2: 75 percent / TsOH / methanol / 2 h / Heating 3: 76 percent / Jones reagent / acetone / 0 °C 4: 1.) CF3COOH, 2.) H2, Ni(OAc)2, NaBH4, ethylenediamine / 2.) Ni / 1.) 20 deg C, 24 h, 2.) ethanol, 20 deg C View Scheme

1: 4.2 g / BuLi / hexane; tetrahydrofuran; hexamethylphosphoric acid triamide 2: 75 percent / TsOH / methanol / 2 h / Heating 3: 76 percent / Jones reagent / acetone / 0 °C 4: 1.) CF3COOH, 2.) H2, Ni(OAc)2, NaBH4, ethylenediamine / 2.) Ni / 1.) 20 deg C, 24 h, 2.) ethanol, 20 deg C 5: 1.) Ph3P, 2,2'-dipyridyl disulfide, 2.) AgClO4 / 1.) MeCN, 2.) toluene, reflux View Scheme